That was a simple answer. Maybe it was the right answer too. Warcraft is something like halfway between AOM and an RPG. Very few know about Avernum too.
True you require some patience (for brains - you can always download some walkthroughs - if you wish), but when you complete a quest you congratulate yourself. Don't you?
There is something about the endgame too. I didn't like the endgame. Maybe because the wastelands lack the greenary so much.