Playing Wild Mana 7.44 I was quite impressed by some things the improved Wild Mana AI pulled off (taking into account that the civ4 AI is fundamentally flawed):
The AI sends cavalry to pillage and thus destroys their enemies' economy. And it counters tries to send fast units to do the same in their territory quite often (in one game, though, Bannor managed to pillage every Sheaim improvement with one chariot). I have even seen suicide commandos trying to pillage strat. rescources!
In one game the Elohim used their world spell very efficient: The nominal superior Sheaim conquered one Elohim city, the Elohim took it back and cast Sanctuary. Then again, in the next game, the now nominal superior Elohim lost one city after another to the Sheaim and only used their world spell when their last city was threatened (that is what I call fundamentally flawed: The AI only takes simple nominal values [e.g., total point value of the armies] into account and ignores evidence - like totally f****** *p - although there are algorithms possible to even translate this into nominal values [see Stardock; I hope firaxis will not forget to implement an AI into civ5... and I really hope I will live long enough to see pdp implemented in game AI, well, hope dies last]).
However there things that might be modifiable:
The AI has a tendency to send its best units (e.g., Heroes) out for unnecessary suicide missions, let some wander arround alone without apparent goal, thus making them easy to pick off, or send some out before they are fully healed.
While the infamous stack of doom might not be the most newest trick in the book, it is quite effective. The AI, however, has a tendency to show up with such a stack in front of my cities, and I think I am doomed in fact, but then it splitts up, sending heroes & cavalry into my hinterland, letting its catapults stay where they are, and its infantry retreats.