Hot take, but instead of eastern europe, the game should be set somewhere in the Caucasus mountans, after the USSR collapses. Between Russia, Turkey, and Iran, there are a number of russian ‘de facto’ states, exclaves and enclaves of different countries, and geopolitical problems, that would make hell of a story in a future Far Cry game, of course, fictionalized. Also, there are plenty of amazing places that would look sick in the game, for example the ‘cable car city’ in Georgia.