There are already many improvements, and cataclysm is due to bring a questing flow and zone design overhaul which since we have not seen yet we cannot judge.
I would love to see a lot more novelty or interesting quests, with less of the kill 2 dozen of whatever mob and go fetch said item/talk to said person 10 feet away quests.
http://www.worldofwarcraft.com/commu...allery.html#10