What if the alliance leaders can just declare war on other alliances which sets all members (non-beige) into a state of war with each other until an alliance peace treaty is signed?
Have an overall scorecard etc for the war, but maybe not all those carthaginian peace terms. Have alliance war record on the alliance page of course.
Would be best as a flavour only fame/infamy thing. I don't think there is ever any need to reward abstaining from warfare in a 'Politics and War' game..
When I joined this game, I was promised that all the players would be saints and nobody would do anything to annoy me, ever. Now it looks like I was lied to and I don't know what to do with my life anymore!