In my opinion a few 8 months more (release date: December 2012) would have made DIII a more balanced game. Again that's just a hunch shared by others too: it sounds like the game was released somewhat prematurely:
Right now some aspects feel a bit rough around the edges (the pricing / quality of items and how some classes have it - relatively - easy on higher difficulties).
Anyway Blizzard said it still considers DIII a work in progress, and serious patching is on its way.
To be honest I really think Blizzard should have taken its time and release the thing when done, they shouldn't have listened to those impatients b*****. Right know people have paid 60 bucks for a fine game that will be well-balanced around next year (rough guess).