I'm guessing this is the right thread for EB2.1b BAI feedback:
The open battle AI is soooo much better. No longer too passive. The siege (defensive) AI seems unreactive - but at least makes more use of the city centre in initial deployment to ensure a bloody last stand. Also now usually place archers on the walls instead of the centre. Without the 3 minute control timer it is also more difficult to clear away the last of the garrison which are lining the walls still. At least this mean you have to kill or rout every defender now which is good.