The game that isn't challenging isn't really all that fun at all.

Granted, if I loose to an enemy too often, I usually burn a few of their cities to the ground.

I hate to say it, but the fact that you lose battles because of AI tactics is awesome. Usually, they just muscle through with numbers and bonuses, but not with actual strategy.

I lost a battle to the Arverni that I had been winning because they wedged their cav and charged my center. I lost half of my army, but was ecstatic, because it was a setback! Wow! Awesome! The AI actually outsmarted me for once.

It gets boring winning battles with massive casualties on the enemy side, and almost none on yours.