Well what I did not like about the AI is that it gets messed up about its long term plans if it is isolated.
In my first game(and I wont it via Space ship
) I discovered the Sioux pretty late around 1850 .Since I am playing on epic I was a bit advanced for my age getting close to the last era.Anyways I went to scout with my 3 leftover infanry units to check for nearby Russian citys(the bad girl owned an entire continent and tryed to invate+settle on my island) and suddnely I find this isolated civ that is still in MEDEVAL age.
Ok well we have seen that happening in Civ4 and 3 as well but wait there is a twist to the story.
That guy had !!15!! citys and 3 citystates to boost him up. SRSLY?!
The other beef that I have with the AI is that it had poor decision making when attacking city states.See city states are made so that they tech evenly with the best 2 civs research wise.So if I have tanks you can bet they can make them too.That being said my Suleiman buddy (before I wiped him out) attacked Buchorest(a military city state) with knights and some weird musket men and a tribushet the 4 infantry units + a 48 defence city. Again SRSLY!?
The last but not least problem I have with the AI is that if you have a militaristic civ with 2-3 other non agressive AI civs around it you can bet 100 bucks that the militaristic civ will EAT THEM ALIVE.
In my case Catherine here owned ghandi and Darius for breakfast.But when she did and dominated he continent she stoped doing ANYTHING else but try and create as many citys she can while completly screwing her science and economy.
Ok in the end I was hardpressed to keep her of my island but in Civ 4 if you have a 30+ city agressor you can bet he will either come knocking on your door with a huge ball of units or will eat you science/culture wise.
So yeah if you play on the weakspots of the AIs you can easly own them.
I hope that on the higher difficulties this will not be the case.(I played on prince btw)