Sounds very interesting! (BTW I also do really like Stellaris!


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Awhile ago I'd been thinking for some time about potential techtree/progress options for M:C and 2071 together with Nightingale; I wrote a few thoughts/comments below.
Investment of Yields for research/progress:
For me, one big point of interest in the techtree system originally made by Kailric for M:C and 2071 was the ability to invest certain Yield types to progress in certain areas of research (though you could also mod some techs that did not require any Yields to research). This adds a lot of strategic interest to mods with large numbers of Yields (like WtP and 2071) where many Yields otherwise become very generic/similar in their role (mainly all shipped and sold to Europe and converted to cash).
In this scenario, it adds a lot of interest/uniqueness if a player wants to make progress in a specific area, and is motivated to acquire and invest some of a specific Yield or Yields to do so. This gets even more interesting if specific techs/progress can provide targeted benefits relating to specific Yields/Terrains/Features/Bonuses, and availability of choices may be partially random as you describe - the player could have to make some really nice decisions considering available options, resources and terrain in the current game situation, and this would add to replayability. Anyway, I'm not sure if that would be necessary for most WtP content but the ability to have some advancements use investment of a Yield would be cool.
SP Points/Categories:
I do like the overall concept of SP categories, but this also raises some design questions to think about:
* If progress relies mostly on getting points in an area that get passively accrued, we'd need to be careful to avoid a self-reinforcing feedback loop for players who may be too easily getting far ahead in that area (e.g. if a player who builds a massive navy also simultaneously acquires free advancements to many naval abilities and construction, the effect on balance could become a runaway feedback loop rather than a good self-balancing mechanism).
* For deeper gameplay, it could add interest to have players make a strategic decision to invest resources in future progress, rather than passively getting further bonuses if you're doing well overall. I.e., in the example above, it's more compelling for the player to have a strategic choice: do I want to focus more on investing to build a massive fleet of ships to overwhelm the enemy with numbers, or instead prioritize using some of those resources to invest in naval advancements, and build a smaller/focused fleet that has some unique tactical and technological advantages?
* Another way to mitigate a runaway feedback loop and provide a good balancing/catchup mechanism would be a bonus to research in a Category based on the progress of other players. (This is also natural/realistic and seen often in similar games due to diffusion of knowledge). Enhancing this bonus for AI players at higher game difficulty levels by applying a Civeffect using handicapinfos.xml would be a nice way to flexibly balance any difficulty there. It could also be interesting to be able further enhance this kind of "shared progress" diffusion via diplomatic agreement, or a Wonder similar to the Library of Alexandria wonder in Civ.
* In your view, would the player be researching/developing one tech/SP at a time, or simultaneously in every one of the 12 categories? The latter option would be more like Stellaris (3 categories simultaneous), but realistically could get confusing for players with 12 categories, and it would be hard to let players choose where to focus their main Research/Knowledge output (they may prefer to focus on one at a time). But in the former option, it likewise might get awkward to have 12 points continuously accruing throughout the game in separate banks and then get "spent" in bursts.
With all that being said, I do see some appealing aspects to getting progress points as you describe (it gives a sense of achievement like FF points do). Maybe there could be some way to integrate progress points while still needing some strategic investments by players. For example, if SP points don't get "spent" like FFPs but instead accrue on a permanent track measuring societal progress in that area. You could then use it as a progress threshold to unlock further advanced options, rather than a currency (i.e. to have more advanced progress options become available in that category, you must have accrued at least XX SP points in that area). You could also consider using progress on the SP points track to apply a discount to the amount of general Knowledge/Research points you need to develop things in that area. Now you have me thinking.. could it even be cool to explore a Social Progress victory as an option?
It is also a very good idea overall to partition techs/progress into several categories/trees (though with 2071 I had not been as ambitious as 12 lol!) This creates further interesting possibilities to have a Trait or Civeffect giving a boost to progress in one specific area. If using a partially random deck, it could also be neat to let a Civeffect boost the number of available options in a certain category (e.g. with a socially visionary leader or advancement, you become able to choose from 2 options in the Society category rather than 1).
Anyway, hope those thoughts are helpful!
I had started on a template awhile back listing some potential interesting gameplay effects that could be applied by techs (most of which could be applied through the Civeffects system), I will see if I can dig that back up.
