I'm quite slow in wars, however entertaining to watch these ballista elephants and siege onagers attacking advanced shielding
it's highest possible difficulty in game too, but still, AIs are doing better than they used to. There's some point when having like 150 cities, that conquering more makes quantity of micro unbearable, also I'm using alt click to add buildings to queues in every city, and later than atomic era queues become very complex due to prerequisites (such as: after conquering new city, can't queue everything in single turn, but must do it separately, like, university, research labs from various areas like biology or microbiology, etc.) I would probably keep conquering more in later ages, if managing cities on different stage of development was easier. If I only have 150 cities on earth and past atomic era not adding more, I can easily build everywhere anything new that is recently researched, by alt+click on capital city