Originally Posted by fadedc
More classes are always welcome. Have you seen how many skills already exist though? There are well over 100 per class. I'm not saying that I'd object to more skills, but I wouldn't exactly consider that a high priority.
Overall though, I don't think Blizzard considers the lack of skill trees to be a loss that needs to be made up for. I think they consider it to be a strength that adds to the game.