With games with "good" AI it that knows your moves too quickly and counters them too easily or efficiently(read robotically). Usually, these games give the AI cheats galore such as being able to build up faster than humanly possible. That's what turns me off to RTS's in general.

Rome Total War with it's faults is a step towards what I think is good AI. I'm not saying Rome has good AI, in fact it's moronic at times. What I liked when I started playing, was how the AI is beginning to play to the same rules as the human. It still gets some cheats. But I liked how fallible, or human, it seemed to be. In battle it makes tactical mistakes, but it is also capable of pulling off brillant manouvers. And in campaign each faction is not some kind of generic Napoleon or Sauron with different units. Each his different goals for bettering their nation-states. Spain for example is Isolationist and in my game Allies with other factions surrounding my own in self-defense. It's intent is to protect not expand its borders.

Now obviously these features are implemented poorly in the game. Spain doesn't build up much of a self-defense force and is crushed. But they're there for future games/expansion packs to build upon.

I'd pick this game over RTS's because I don't feel like this is The Matrix and Agent Smith is controlling the enemy. I don't want to have to be Neo.