Collecting Ideas for a Rise and Fall of Civs, Dynasties, Cultural Pressure or Ethnicity Mod for Civ6

[Zegangani]

I'm currently working on a Mod Series that introduces many new Mechanisms/Systems to the Game (and altering some existing ones), which work like the NFP Game Modes (that you can enable/disable as you desire), but are more fleshed out/detailed and interconnected with the Game's existing Mechanics. There are 6 Mod packs planned (maybe more depending on how this series will succeed), with each including a set of new Mechanics (some big some small) or reworked existing ones. The Aim of this Mod Series is to flesh out/rework the existing Mecanics, make them more interconnected and introduce new Ones (which are very influenced by Ideas I gathered from this Forum - with many that tackle the Late Game Lag Issue). And I'm sure everybody will find something that they will always want to have enabled .

Given that these Mod Packs require a lot of Time to be finished, I decided to release them similar to how the NFP Packs were released: one Mod Pack each 1.5/2 Months, with the first one comming in October. Each Pack has a clear Design/Theme/Objective, and most of the Mechanics of the Packs are already designed, they just need to be coded and polished. (More Infos will come when the First Mod is released)

The Theme of the 3rd Pack is Empire Management, and I'm currently struggling with a Mechanic that I want to Include in that Pack, which is "Rise and Fall of Civilizations". I had a Conversation with @Boris Gudenuf who Suggested " 'Alternative Progressions' . . . with 'internal' changes like the Dynasties/Leaders with different Uniques attached or available". I really like this Idea, however, it would be a huge work to design all the progressions for all the Civs and much more work to code all of that. Especially since the Goal of this Mechanism is to allow for dynamic Progressions, so just including IRL cultural changes wouldn't suffice for this, but aternative/fictional Outcomes of Cultural Changes are necessary (like Aztecs Conquering Portugal/Spain).

As you can see, even if it's a simple Concept, it's clearly a huge undertake that requires a lot of work/research and Time. So I'm not really sure how to tackle this, because I really want to have a Culture changing Mechanic included in this Mod Series.
Therefore, I wanted to ask you, the Civ Community, what would be of more interest to you:

- a dynamic Rise and Fall of Civs Mechanic (which will take the route of fictional Progressions as well as having the IRL Progressions of Civs),
- hardcoded Culture change (such as Rome>Byzantium (but what about Greece?)) that happen after each/2/3 Era(s) (I'm not a Fan of this tbh),
- a Dynasty Systeme that allow for picking a Civ Dynasty from a pool after each/2/3 Era(s),
- a Cultural Pressure mechanism that affect/get affected by the Authority/Stability of an Empire, with Pressure being exerted with Culture as well as Conquest (culture presence of previous owner/conquerer), and Trade.
- an Ethnicity Mechanism that makes each Citizen have a lineage/ancistery (or nation), ( Yes, this isn't a Culture changing systeme, but something that expands the Culture Mechanism - admittedly, I can't see how this can be Fun/interesting to play with),
- (if you have another Idea please tell me in the Comments)...?

So I would like to know which Mechanism of the above (or do you rather want a combination of some of these Mechanisms?) you are more interested in (and why), how would you like it to be implemented/how would it look like/work in Civ VI, and how should it interract with the existing Mechanics (or potential new Ones), such as the Loyalty Systeme.

As mentioned above, this Mechanic will be implemented in the third Mod Pack, which most likely won't be released before January, so enough Time to gather the necessary Ideas and Suggestions from you to implement before I finish the first two Packs, so I can immediately start working on it after that.

I'm not knowledgeable enough about History to feel comfortable implementing any of these Mechanisms on my own without consulting others who might be well-versed in History to know what would work and what wouldn't, how the fictional Progressions should happen or how the Cultural Pressure should work (I want it to be as realistic as possible). So I'm asking you guys to share your thoughts about this, if you have already a Concept/Design of such a Mechanic, or would like to think about one, feel free to post the details here, and if you want to go a step further and help me research/design the progressions of the Civs I would be very happy about that. Thank you!

(I noticed that a lot of People recently got interested in Cultural Changes in a Game (the Spark of Humankind has set Fire), so this is the chance for you guys to suggest/discuss such a Mechanic for Civ VI )

Note:
- You can be as creative as if suggesting things for a new Civ Title. We don't have to stick to the Game's Design. It's a Mod.
- I won't make Culture Changes ala Humankind's Random Cultures.
- As this Pack's Theme is Empire Management, it won't include an Ideology Systeme, since this latter has more to do with Diplomacy, which is a theme for another Pack. But feel free to share your thoughts about an Ideology Systeme if you like.
- Things that have to do with Empire Management/Culture, but can't be modified: Tourism/Loyalty Pressure on/from (a) specific Civ(s). Which doesn't allow for dynamic Tourism or Loyalty Pressure.

 

[Buktu]

I voted for cultural pressure. If I understand your idea correctly it will work a little bit like in HK? You build alot of culture or trade alot to get influence in other empires cities.
Ofc there are no HK like civics but you could still grant science/culture (wether its raw yields, heurekas/inspirations or even complete techs/civics) from this as a little catchup mechanic. And it comes at the cost of loyalty in border cities (I hope that is possible since it is against a specific city and not a specific civ) which might flip more often with such mechanics makeing a game more dynamic.
You could also tie in diplo favour here so the more influcene you have in other empires cities the more favour you get and grant some other diplomatic actions, like a new casus belli.
Maybe citizens from want to migrate towards another empire if they are under heavy influence.
This has also the potential to reduce the effectiveness of war for the human player if conquerd territores are still under the cultural influence of their former owner. Maybe they rebell faster or spawn partisans even before they flip independant. Maybe if the cultural influnce of their former owner is high enough they rejoin their empire directly.
It can also affect city states/envoys. Lets say you get a free envoy in every cs under your influence at the start of a new era.
Something really crazy would be a new (or updated?) victory condition requiering to have all civs under your influence.

I guess there are alot of great ideas in this concept that I am missing right now (and some might be stupid, its already 3 am here).

 

[Zegangani]

I voted for cultural pressure. If I understand your idea correctly it will work a little bit like in HK? You build alot of culture or trade alot to get influence in other empires cities.
Ofc there are no HK like civics but you could still grant science/culture (wether its raw yields, heurekas/inspirations or even complete techs/civics) from this as a little catchup mechanic. And it comes at the cost of loyalty in border cities (I hope that is possible since it is against a specific city and not a specific civ) which might flip more often with such mechanics makeing a game more dynamic.
You could also tie in diplo favour here so the more influcene you have in other empires cities the more favour you get and grant some other diplomatic actions, like a new casus belli.
Maybe citizens from want to migrate towards another empire if they are under heavy influence.

Those are all great Ideas, thanks for the Input!

I haven't played Humankind yet, so I don't exactly know how the Cultural Pressure works in that Game (I will have a look at the Humankind Wiki later on though, to see how it's done there). But yes, the more Culture you have (including building Wonders/acquiring lots of Great Artists/Writers/Musicians, having Great Works/Artifacts, Happy/Loyal Citizens...etc) the more the Cultural Pressure you exert on other Empires, which also increases the Pressure through Trade Routes.
I really like how you tie this Mechanic with already existing ones, such as Eurekas/Inspirations (much better than raw Yields) which might stack (boosts from multiple sources, which might end with the Civic/Tech getting unlocked without even directly researching it), and Diplo Favors. (I haven't thought about both Ideas tbh, which is exactly the reason why I opened this Thread, there is always something that you haven't though about, but others have)

Immigration will be it's own Mechanic that will come even before this one, but I will tie all the Machanics that fit together. Citizens migrating to Civ's that put the most Influence on them is a nice way to connect these 2 Mechanics.

This has also the potential to reduce the effectiveness of war for the human player if conquerd territores are still under the cultural influence of their former owner. Maybe they rebell faster or spawn partisans even before they flip independant. Maybe if the cultural influnce of their former owner is high enough they rejoin their empire directly.
It can also affect city states/envoys. Lets say you get a free envoy in every cs under your influence at the start of a new era.

That would be a good way to compensate the Power of Conquest and restrict it's effectiveness. And I completely agree that if the Cultural Influence of the former owner surpasses the Pressure of the Conquerer, the City should immediately flip to it's former Owner (or original Owner - will be tricky to implement if already defeated in the Game).

CS Envoys from Culture Pressure is another great Idea!

Something really crazy would be a new (or updated?) victory condition requiering to have all civs under your influence.

The 4th Pack of the Mod Series will have lots of Mechanisms that affect the Culture Aspect of the Game, so I probably won't make a Culture Victory Condition rework till then. But if enough Time is left before the next Pack (finishing it before the set deadline), I might make a seperate Culture Victory Condition for this (not as a New Culture Victory, but as a reworked version that can be enabled/disabled).

There are many Things that could affect Cultural Pressure/Influence, including Vassalage, and the Packs' Mechanics will be interconnected with each other wherever applicable (with new Packs updating previous ones), so, as said in the OP, you can be as creative as you want with your Ideas, the only thing that can come in the way is Modding Limits, but since you might not know to how extent we can go with modding, just throw your Ideas here, I will let you know if something isn't moddable or too AI disabling.

 

[Hellenism Salesman]

Not sure if this is possible, but I always thought this was a great idea and wanted to share my own thoughts.

(Note: to make my ideas easier to understand and alleviate my excessive use of the word "culture," I've color-coded some of the mechanics I'll be discussing.)

• Culture, the existing resource you're familiar with, is purple
• Cultural Pressure, the new mechanic we're discussing, is blue

I've always had the idea of a Culture/Worldview system that works almost like a fusion of passive religion spread and Loyalty. Every city generates Cultural Pressure based on its Culture output, which effects nearby foreign cities based on distance (think of how Loyalty pressure works). If that city's Cultural Pressure is less than the pressure of a different civ, they will slowly begin to adopt that civ's culture. Once the foreign civ's Cultural Pressure becomes a majority in that city, it is converted to that culture and will generate Cultural Pressure for it.

As an example:
A Vietnamese city is generating +1 Vietnamese Culture Pressure per turn. A neighboring Chinese city is generating +4 Chinese Culture Pressure per turn. Both cultures will influence each other (the Vietnamese city gains some Chinese culture, and vice versa), but because the Chinese city has a stronger Cultural Pressure, it will outpace the Vietnamese city and eventually convert it to the Chinese culture. Once converted, the Vietnamese city generates Chinese Cultural Pressure, gradually increasing as long as it is under Chinese cultural influence.

That's the gist of it. I think all it would need is some effects and bonuses, which I have a couple ideas for.

• Foreign cities with your culture established as a majority also generate you Culture, the resource
• City-states under your cultural influence could also generate Culture, as well as Influence Points and Envoys
• This is the most dramatic idea and likely the least possible, but how about when a city (either belonging to a civ or a city-state) is fully converted to your Cultural Pressure, it joins your civilization? Like, the cultural assimilation has become so great that the people side with your government more than their own. Come to think of it, this is actually similar to what Eleanor's ability tries to convey, but only using the limited currently-existing systems.

I have no idea if I properly explained any of that or not, and if there's any confusion about the system, feel free to ask questions. You may end up finding a logistical loophole to which I have no answer, but that's what discussion is for: making an answer ourselves.

And, I'm not sure if this is helpful to you or not, but I thought I'd give my ideas on the system in hopes it could spark some inspiration. I really admire what you're trying to do here and I'm excited to see how this turns out. This addition is going to have a wonderful effect on the game.

 

[Boris Gudenuf]

Culture and Cultural Pressure is a fascinating concept, and well-documented IRL, but what does it mean in-Game?

First, a good case can be made that it has little effect on 'flipping' cities or regions: ALL the Greek city states shared very similar cultural attributes throughout the Classical Era, but they fought each other tooth and nail and nobody ever willingly became subservient to anybody else, or even cooperated for very long. Ditto the Italian "renaissance" city states. A case could be made for a pretty common culture in the Scandinavian countries in the last century or so, but I remember hearing a Norwegian (student, in college) using language to describe the Swedes that I would reserve for child-molesting Nazis - sometimes, Familiarity really does Breed Contempt.

So, I would say that at best, Cultural 'dominance' makes it easier to assimilate another group/city/region, but only after you have gained political control over them by other means: usually military, but potentially economic or religious (and when talking about organized, heirarchial religions, they cannot be modeled the same as the more amorphous 'culture')

Which may be where we can make Cultural Dominance really useful in the game.

There have been some complaints as well as raves for Humankind's War Support mechanism, in which the end of a war comes when the digital population decides it has had enough, not the player. I happen to like it, but I think it could be 'tweaked'. Like, your people are more likely to fight 'To The Death' (of the other guy, at least) if they are or represent a really 'alien' Culture - War Support will stay higher longer. On the other hand, fighting your twins is harder, without a generated Cause of War (Causus Belli) from another source: diplomacy, economics, specific Unacceptable Actions by the proposed enemy. And as the war drags on, even the worst of all that will be forgotten as people get tired of fighting somebody who is "just like us (almost)".

And after the war, Culture should be one of the primary determinants of how easy or how difficult it is to turn a newly-acquired/captured City into your own. An imposed alien Culture will be deeply resented, and will spawn resistance/rebellion/uprising/"liberation" movements. Conquering a City whose dominant Culture is not your own, and has a different Religion, should require some major long-term effort to make it fully your own, and during the transition 'resistance' (the good old British Army term: "Dumb Insolence" or passive resistance, is appropriate) will reduce any gains you get from it: 0 Culture, obviously, but also less Production, Science, or anything else.

Parenthetically, Difficulty in Assimilation is a problem the Europa Universalis game has had Forever. Play a game from the Start, and by the early 16th century there are almost no small states left in Europe, because they inevitably get conquered by even slightly larger neighbors. IRL, in 1806 Germany alone still had 1500 separate political entities, ranging from City States you could amble across in a few hours to States like Prussia or Bavaria that were major players in European diplomacy and conflict. It was just too hard to turn even close neighbors who were used to running their own affairs with their own, familiar set of aristocratic Imbeciles in charge into even semi-loyal citizens obeying your own Imbeciles In Charge.

The answer to the Runaway late game Military Juggernaut is to make it harder for them to get positive advantages from their conquests - short of pulling a Mongols in Afghanistan Move and simply depopulating the place: effective at removing all resistance, but leaving nobody to assimilate, and giving you the benefit of the scenery, but no Production, Science, Food or Culture at all.

Cultural Diffusion/Domination and (slow) assimilation and (rapid) resistance from same would be the perfect mechanic to provide this.

 

[Zegangani]

@Hellenism Salesman , everything you said is completely comprehensible, and all of your Ideas are moddable, though there is one thing that would either need a "detour" way for making it, or (otherwise) it could be easily done but at the cost of something else, but more on that Later. Anyway, those are all good Ideas, that indeed help me to visualize the Picture of how the Cultural Pressure/Diffusion might look like. Thank you!

I've always had the idea of a Culture/Worldview system that works almost like a fusion of passive religion spread and Loyalty. Every city generates Cultural Pressure based on its Culture output, which effects nearby foreign cities based on distance (think of how Loyalty pressure works). If that city's Cultural Pressure is less than the pressure of a different civ, they will slowly begin to adopt that civ's culture. Once the foreign civ's Cultural Pressure becomes a majority in that city, it is converted to that culture and will generate Cultural Pressure for it.

Taking Boris Gudenuf's estimation of Cultural Diffusion having little effect on City flipping under consideration, I think a good way to make this, is by making the Culture output of a City define how strong the Cultural Pressure on Neighbours, through Trade or with Religious Spread, as well as the resistance from acquiring another Culture (making it more difficult to assimilate Cities with stong Culture Output) will be, in combination with Cultural Pressure being less powerful in the early Game (with Religion having more effect on it than Economics) but becomes more relevant in the Late Game (especially with Economics, less with Religion). But a City adopting another Culture shouldn't mean flipping to someone else, but: How about inhereting traits of that Civ's Culture (Think of the Cultural Groups from "Sui Generis" Mod, but for individual Cities) in form of new Abilities (Civs will have Cultural Traits (Not Civ Traits, because they aren't designed for individual Cities) that their Cities can benefit from, but once a City gets culturally influenced by another Player, it will lose its current Trait in exchange to that Player's Trait)? So "Culture flipping" (getting Influenced by another Player's Culture) wouldn't be a noisance that you try to prevent (at all costs in some cases), but something that you might even strive for, because you can inherit a new Trait Ability this way. (just colonised the northern part of the Map that's just Tundra/Snow? if those Cities get cultural Influence from Neighbour Russia, they might gain an Ability that helps them getting used to the Terrain)

Foreign cities with your culture established as a majority also generate you Culture, the resource

I am afraid this might be too powerful, especially in the Hands of the Human Player. But maybe a similar way of gaining Culture like having envoys sent to Culture CSs (+X Culture for having Y in your Cities)?

City-states under your cultural influence could also generate Culture, as well as Influence Points and Envoys

It's good that you mentioned City-States. We can't make a Player generate Influence Points towards a specific (culturally dominated) CS, so perhaps gaining an Envoy there once the Culture Assimilation is signed and sealed, and also after each Era transition if it's still Influenced by that Player's Culture (Dominant Culture) might be a good way to gain something from CSs. We can also make the Player that have Cultural Influence over a CS, also gain its Suzerain Bonus (only), without having political Control over it and the benefits of that (Levying, following you into War/Peace).

This is the most dramatic idea and likely the least possible, but how about when a city (either belonging to a civ or a city-state) is fully converted to your Cultural Pressure, it joins your civilization? Like, the cultural assimilation has become so great that the people side with your government more than their own. Come to think of it, this is actually similar to what Eleanor's ability tries to convey, but only using the limited currently-existing systems.

This is indeed possible to make, however, the implementation is tricky, beceause there are 2 Ways to change the owner of a City (there is no direct way to change ownership of a City) and both have some unwanted side effects:
- using the City "Deal" to trade a City (like when ceding a City Diplomatically in a Deal with the Owner), which has 2 unwanted downsides/effects: it's restricted to Major Players only (so we can't do this with City-States), and because this will be made behind the scenes, it would keep the positive relationship modifier of Trade between the two Players, which we don't want.
- saving all the City's data (Name, Plots owned, Pops, Buildings/Districts/Improvements built...etc), removing it from the Map, and then build it again (using the saved data) for the new Owner. However this will have negative side effects of the City's Original owner being the new one, not the old, so the City won't be able to be liberated to it's actual Owner. There might be a way to solve this by reworking the City Raze/Liberate PopUp, but the AI wouldn't make use of this (Do they even Liberate Cities?).

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First, a good case can be made that it has little effect on 'flipping' cities or regions: ALL the Greek city states shared very similar cultural attributes throughout the Classical Era, but they fought each other tooth and nail and nobody ever willingly became subservient to anybody else, or even cooperated for very long. Ditto the Italian "renaissance" city states. A case could be made for a pretty common culture in the Scandinavian countries in the last century or so, but I remember hearing a Norwegian (student, in college) using language to describe the Swedes that I would reserve for child-molesting Nazis - sometimes, Familiarity really does Breed Contempt.

So, I would say that at best, Cultural 'dominance' makes it easier to assimilate another group/city/region, but only after you have gained political control over them by other means: usually military, but potentially economic or religious (and when talking about organized, heirarchial religions, they cannot be modeled the same as the more amorphous 'culture')

Thanks for the Insights Boris Gudenuf. City (ownership) flipping through cultural Dominance shall be removed from the List. Aside from Cultural Dominance through Political Control, Economics will play a big Role in Cultural Influence, though I can't expand on this in the 3rd Pack but in the 4th, whose theme is "Economics" .

There have been some complaints as well as raves for Humankind's War Support mechanism, in which the end of a war comes when the digital population decides it has had enough, not the player. I happen to like it, but I think it could be 'tweaked'. Like, your people are more likely to fight 'To The Death' (of the other guy, at least) if they are or represent a really 'alien' Culture - War Support will stay higher longer. On the other hand, fighting your twins is harder, without a generated Cause of War (Causus Belli) from another source: diplomacy, economics, specific Unacceptable Actions by the proposed enemy. And as the war drags on, even the worst of all that will be forgotten as people get tired of fighting somebody who is "just like us (almost)".

I can't see how to adopt this Mechanic of "War Support" to Civ 6 in a meaningful way. We can try to prevent a Player from certain Cassus Bellis or Attacking specific Players (with same Culture), or we can also reduce the Combat Strength of your Units when fighting against a Player with same Culture in its Territory (no way to check the owner of the opponent unit/city to make this work outside of its Territory as well as inside). Though, a Combination of all of that might work better.

And after the war, Culture should be one of the primary determinants of how easy or how difficult it is to turn a newly-acquired/captured City into your own. An imposed alien Culture will be deeply resented, and will spawn resistance/rebellion/uprising/"liberation" movements. Conquering a City whose dominant Culture is not your own, and has a different Religion, should require some major long-term effort to make it fully your own, and during the transition 'resistance' (the good old British Army term: "Dumb Insolence" or passive resistance, is appropriate) will reduce any gains you get from it: 0 Culture, obviously, but also less Production, Science, or anything else.

The answer to the Runaway late game Military Juggernaut is to make it harder for them to get positive advantages from their conquests - short of pulling a Mongols in Afghanistan Move and simply depopulating the place: effective at removing all resistance, but leaving nobody to assimilate, and giving you the benefit of the scenery, but no Production, Science, Food or Culture at all.

This is the most important Part of the Mechanism, restricting the Benefits of Conquests. Resistance from the City's Citizens through rebellion (rebels spawing on that City's Territory) and reduced/missing productivity (less/no Yields generation), as well as increased Amenity requirement for the Citizens (1or2 per each Citizen, instead of 1 for 2 Citizens - among other things that would require active efforts to hold the City) would be a good way to tame the lust of Conquest.

As, suggested by Buktu, Immigration could also affect Conquest. With a conquered City's Citizens migrating/escaping to their original Owner's Cities or neighbouring Cities, if the City's Culture wasn't under the Influence of the Owner, but others.

Parenthetically, Difficulty in Assimilation is a problem the Europa Universalis game has had Forever. Play a game from the Start, and by the early 16th century there are almost no small states left in Europe, because they inevitably get conquered by even slightly larger neighbors. IRL, in 1806 Germany alone still had 1500 separate political entities, ranging from City States you could amble across in a few hours to States like Prussia or Bavaria that were major players in European diplomacy and conflict. It was just too hard to turn even close neighbors who were used to running their own affairs with their own, familiar set of aristocratic Imbeciles in charge into even semi-loyal citizens obeying your own Imbeciles In Charge.

As said above, I can see Religion having lots of influence on Cultural Diffusion in the Early Game, and less in in the Late Game, where Economics take the Lead. But the Cultural Influence will still be less impactful in the early Game, but slowly growing in effectiveness, with being more impactful in the Late Game (Industrial Era onwards).

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All this Conversation and your Ideas and Suggestions contribute to my conviction that a Cultural Diffusion (a better Name than Cultural Influence/Pressure) is arguably the best choice.

So I think I will put off the "Rise and Fall of Civilizations" Mechanism until the End of this Mod Series (even though it is one of the first/main Mechanisms that I wanted to include in it), where I'll have more time to just focus on that. But it doesn't mean that yo shouldn't share your Thoughts/Ideas about it. Feel free to post your Thoughts on anything relevant here.

I will post a (not too) detailed features List of the First Pack of this Mod Series later this Week (if I find enough Time to organize the chunks of texts filled with typos because of quick writing ), so you can share your Thoughts on them, and I may also modify something if you have some better Ideas of how it should be. (All the Mechanics will be subject of changes throughout the whole Time I will be working on this Mod Series, so People can still Suggest things for already released Packs, and I will try to update the Mechanisms with every released Pack (and maybe in the inbetween Time too))

 

[Alexander's Hetaroi]

As far as ethnicity is concerned, I think that if you were to implement that into the game the dominant ethnic group of a particular city should influence the type of culture generation.

Going back to the example of Vietnam and China: If a majority of the Vietnamese city citizens have are ethnically Vietnamese they will still be promoting their culture. If through conquest, or some sort of immigration mechanic, where the Chinese citizens become more prevalent it would be easier to flip it to Chinese culture.

As a result there is the possibility that later in the game that particular Vietnamese city might gain many foreign tourists from China, because of the flip of culture.

 

[Zegangani]

As far as ethnicity is concerned, I think that if you were to implement that into the game the dominant ethnic group of a particular city should influence the type of culture generation.

Going back to the example of Vietnam and China: If a majority of the Vietnamese city citizens have are ethnically Vietnamese they will still be promoting their culture. If through conquest, or some sort of immigration mechanic, where the Chinese citizens become more prevalent it would be easier to flip it to Chinese culture.

I've decided to go with the Cultural Diffusion Mechanism for the 3rd Pack, but this doesn't mean that there is no chance for me including other Cultural Mechanisms later on.
I would love to see an Ethnicity Mechanism in the Game, which, as you mentioned, can also be tied to Cultural Diffusion and Immigration. I think a Mechanic that makes each Citizens have more personality with Ethnicity/Nationality/Religion, Amenity Requirement (based on City Economics), Ideology, Health...etc would be good enrichment to the individuality of Cities and their Citizens.

Although we can't choose a Citizen to be, for example, a Scientist only (modding wise), we can still set the number of Citizens that can be scientist (which may require more amenities than the average citizen) and make that Number affect how effective the Specialists in Campuses are. Example: a City with 10 Pops can only have 2 Scientists, if the City's Campus has 2 Scientists/Specialists, they all will work at full efficiency, meaning if scientists of Campus in that City generate 3 Science per turn each, they will generate this same amount. However if that City decided to assign another Citizen to the Campus (so it has 3 in total), only the 2 Scientists will generate 3 Science per turn, the new (apprentice) worker will only generate 1 science per turn. We can also make that the new apprentice increase in efficiency and slowly become a full scientist with time (having worked in a Campus for a set amount of Turns), but there is no way to keep track of individual Workers as Citizens (with theit individual Attributes - they don't have unique IDs like Units have) and how long they have worked in certain Districts/Tiles, which would be an Issue when constantly reassigning plot workers/specialists. so perhaps the "Apprentice" methode isn't a good way to go with this. Just setting the amount of each Specialist Type per City (increases with Civics/Policies/Government/Techs...etc), and the efficiency of non Specialists in Spec Districts should suffice for this.
This way, Specialists will have more effect on the productivity and maintenance of a City.

As a result there is the possibility that later in the game that particular Vietnamese city might gain many foreign tourists from China, because of the flip of culture.

Unfortunately, as mentioned in the OP, we can't modify the Tourism or Loyalty pressure on/from specific Civs, which in this case will be the Culturally dominated and/or the dominant ones. There is a modifier that should have worked for this, but it only checks for the owner not the subject (other faction), so it only works globally (tourism pressure on all civs in the Game). Otherwise it would have been easy to even Fix the Monopolies Bug (at least I tried it).