Although I feel that Civilization VI diplomacy is some of the best I have seen in the Franchise, there are still some additional Interactions-both Major Civ & City State-that I would love to see-perhaps in a 3rd Expansion or in DLC's. It probably won't surprise you to find most of the ideas here are slightly re-worked versions of earlier game mechanics (Edited 27/01/19) State Religion/State Ideology: I won't lie-though I found the State/Non-State religion effects on Civ4 Diplomacy extremely OP, I really did like the concept. Done correctly, with the diplomatic relations bonuses/penalties building gradually over time-& being impacted by player actions & how the AI Civ views religion (so sharing a State Religion with a Civ will cause a gradual improvement in your diplomatic relations modifier-but that will increase faster if you start actively converting cities to that religion and/or removing non-state religions from your cities), I feel this could be a great addition back into the game. Ideologies was a great idea from BNW, & one I'd like to see return......with many of the same features-like Tenets & Tourism/Loyalty effects. I could also see certain Ideologies having effects on certain Policy Cards assigned to your government. Like a Militaristic Ideology might increase bonuses from cards in military slots. State Religions & Ideologies could also have a number of different impacts on your domestic situation as well. 3rd Party Peace Deals: Why don't we have this already? I really want the ability to step in between two warring Civs & use my world standing to urge one side to make peace with the other. Likewise, I want the ability to urge a Civ to end a war with a City State (& maybe gain an envoy with that City State as a reward). Cease Fires (1st & 3rd Party): As has been suggested, this is basically a mutual Promise to cease hostilities for x turns. Re-launching hostilities before the time has expired will earn you grievances, whereas keeping the promise will earn you favour. 3rd Party War declaration: using diplomacy to urge a Civilization to declare war on a 3rd party (as distinct from a Joint War) 3rd Party Trade Deals: This is from Civilization 4-the ability to ask a Civ to either start or end trade with a 3rd Party Civ. Pacts of Secrecy: This was a great Civ5 idea that was executed horribly-because it showed up to early in both the time-line of each game, & the time-line of the development of Civ5. The way Secrecy Pacts were introduced made them meaningless, as there was no way to secretly undermine a 3rd Civilization. However, with Privateers & Spies in the game, a Pact of Secrecy makes much more sense. 3rd Party Wars & Trade Cessation (see above) could be another means of meeting the criteria of a Secrecy Pact. Change Religion/Ideology/Government/Policy: Basically a Diplomatic Option where you ask a Civ to change something about their Civilization-be it State Religion, State Ideology, Government.....or even Social Policy.....to one more in line with what you currently have. NATO/Warsaw Pact: By which I mean, multilateral Military Alliances. Even if the option only becomes available with the Cold War Civic, I think it is worth having in the game. Of course, a similar effect could be achieved with multiple City-State Protectorates....see below. Ask About/Trade Communications: If you are friendly with a Civilization, you can ask them their opinion on other Civs they have diplomatic relations with. Also, you can ask to be put in touch with a Civ they have contact with *or* offer to put the Civ in touch with a 3rd Party Civ you're in contact with. This was another great feature from Civ5 & Civ4, respectively. Land Deals: This would require the return of contested tiles (Culture) & could have two distinct facets. The first is the ability to ask for/demand all contested tiles from a neighbour-or to offer to relinquish all claim to said tiles yourself. The other facet would be the ability to purchase contested tiles-at inflated prices-via the normal tile purchase screen.....but at the potential cost of gaining Grievances. City-State Protectorate: As with Civ5, players should be able to pledge protection to a certain number of City-States. Unlike Civ5, I'd place some kind of limit on the total numbers of City States you can pledge to protect, but the benefit of pledging should be the gaining of a free envoy with that City State. However, if the City State is attacked, & you fail to at least denounce the Civilization for doing it, then that Envoy will be lost. City-State Bullying & War: Something I miss from Civ5 is the ability to bully City-States, as well as City-State quests where I was asked to bully another City-State.....even better, it would be cool if a City-State asked you to declare war on another City-State, as a quest. Which brings up the penalties that I feel should exist for mistreating City-States. Bullying a City-State should lose you an Envoy with that City-State (even if you don't have one yet) & Declaring War should lose you 3 Envoys with that City State (again, even if you don't have one yet). Competitive City-State Quests & City-State Quest Failure penalties: What more needs to be said? I really enjoyed these in Civilization 5. Likewise, I'd like to see certain City-State quests with a stipulation that failure will lead to Envoy loss-though I feel these types of Quests would need to be actively accepted by the player, not passively offered (so a quest like City-State bullying would be one that a player would need to actively accept). New Spy Actions: These are actions that would relate directly to diplomacy. The ability to convert a Spy into a Diplomat, as in BNW. Diplomats could be used, in City-States, as a weaker version of Amani, or they could be placed in the Capitals of Major Civs for similar effects as they had in Civ5. They can earn you automatic favour per turn with that Civ, would accelerate the loss of accumulated Grievances & would give you extra Alliance Points per turn (if applicable). You would need a resident embassy to do this though (speaking of which, we need an ability to remove delegations & embassies IMHO). Another Spy Action I'd like to see is higher levels of the "Fabricate Scandal" ability. Namely, an ability to conduct "Election Rigging" & "Coups" in City States. If successful, they would remove 1 to 2 envoys from the leading Civ, & give you an equivalent number of envoys. Though, if court, you'd earn grievances with the leading Civ in that City-State. Such missions would be increasingly harder to pull of successfully than a Fabricate Scandal mission. It would be nice if Spies could gather info on AI Civ intentions towards a third party (Pacts of Secrecy, upcoming informal war declarations, Ongoing Spy Activities etc) that you can pass on to the latter Civ (Intrigue). Likewise, it'd be cool if higher ranked spies could leave behind evidence implicating other Civs in your spy activities .