@comr Best thing is to play some of the new/complex maps and read the POS2 XML to understand what is available today: https://github.com/triplea-maps/the_pact_of_steel/blob/master/map/games/pact_of_steel_2.xml
The AI overview and backlog of improvements are here: https://forums.triplea-game.org/topic/105/ai-development-discussion-and-feedback. I wrote all of the Fast/Hard AI so know all of the algorithms/code for it. It was primarily written to play the standard A&A maps (classic, revised, v3, global, etc) so it performs reasonably well on maps that primarily use similar rules. But if you try to have the AI play Total World War or Civil War, it plays very poorly and doesn't understand many of the features used in those games. Suggestions and contributions are always welcome and you can find the AI code here: https://github.com/triplea-game/triplea/tree/master/game-core/src/main/java/games/strategy/triplea/ai