Apples and Oranges I say.

Though with the growing progress in genetic engineering, we may be able to compare them easily soon.

Still, the balance for blizzard's RTS has been quite good as far as I can tell. Other than that, it is not really my kind of game. I like to control units instead of single thingies. And I really really like TW's major selling point of pick an army and fight with it, rather than also having to worry about economic growth. I don't feel like being a fast-click account-manager. ;) Nor do I care much for their WC lore, eventhough I did enjoy WC1, it went a bit too cartoonish for me after that. WC3 did had a real nice 'league' system at first glance, but I spend too little time to really look into it in more detail. And yes, Blizzard is way way bigger, and its own publisher too right?

AI never challenges a human player I think, unless its a nice game of chess I suppose.