I *hate* playing against cheating AI.
Damn you Westwood! Not only can they easily do 15 things at once, they also cheat for tiberium! So frustrating. Nothing like wiping out their whole army and then having a BIGGER one attack you in 2 minutes. GARRRRRRRRRRRRRRR!
Games with AI for opponents were "fun" back in the day when I had 56k and didnt play online, but nowadays, the best gammage will be gotten online.
If youre looking for a great game thats easy to learn and hard to master, pickup Warcraft 3 and The Frozen Throne(expansion). The single player is pretty okish, and the AI isnt too cheap. The regular multiplayer however sucks ASS! Anyways, play custom maps. Like DotA, TDs, Paintball, MoP, and so on.