Actually, thinking about it, it makes perfect sense to start at level 3 seeing as those first two levels are so boring and underpowered. Of course, what should actually be fixed is the rule system, but obviously with DnD that isn't an option.
Besides, and correct me if I'm wrong, starting at level 3 was already what effectively happened in NWN2's OC where, generally, you reached level three before finishing the tutorial.
I guess the only question left, is whether everyone starts at level 3 or if it depends on the race's ECL.