AI behaviour:
Just finished GOTW 30.
Greece has way more cities and troops than the player:
Things the AI does "wrong":
At one point he parked 8 onagers around ONE city. All the fighting was done at a 2nd city north of that. Those 8 onagers didn't fire more than 3 shots. I parked 2 of my own onagers behind my own city, so we had a nice standoff for 10+ turns. When I moved in, the onagers tried to run, so this whole impressive army of onagers was kept in check (and defeated) by 2 of my onagers, 1 milita, 1 spearman, and 2 archers.
AI is very good at killing exposed units. When no units are exposed, it sometimes outflanks, but most of the time he sits and waits. AI should follow a plan like "collect two waves of troops" and actually go on the offensive.
On multiple occasions I noticed that the AI is very willing to evacuate one of his cities if forces seem overwhelming. AI should take into account how MANY troops he can move to a certain area within the next 2-3 turns. Sometimes there was a huge AI army 1 or 2 turns away, but the AI still evacuated one of his cities right after it was taken or even before that, when it had come close to falling.
Also the AI should not use the garrison of a city with nearly no hitpoints left, just to kill a stray archer somewhere. Sieging cities is only a pain, if there is a troop inside.
Also the AI should probably ignore workers during the war. I mean his own workers and the player's workers. Command points are so precious, there is just no time to move workers around.
Overall the AI is quite decent, a lot better than Civ's AI at least. It killed a lot of my troops when he had his own troops assembled. But assembling his troops seems to be the main problem. Maybe the AI should try to calculate the likely outcome of the next two or three turns, instead of simply playing the "optimal" way in his current turn. But that's a lot to ask for. But then again, the game's wars are won by getting the right troops to the right place and maximizing their firepower over the course of 3-5 turns.
From that Greece game, it looked like the AI was spreading his troops too much. Sometimes, it looked like he had nothing left, but whenever I left units exposed he moved troops in from across the sea to kill or attack any stragglers or wounded troops. So the AI had the troops but they were waiting somewhere.
On one occasion the AI used all of his command points to rescue one single onager that was doomed and surrounded. Onagers are slow, so the cannot retreat very well. Marching one onager 20 tiles across hills isn't going to win a war.
The AI also built way too many onagers.
Overall the AI is really decent when it THINKS it can win a fight. Let's say 9 AI troops vs 6 player troops. But it is terrible when fighting 35 vs 18. It's afraid to lose 15 troops to annihilate 8. And that's about the only real problem with it, I think.