-The shortness of the main quest is a very good thing for me. While I've read reviews that this is a problem, i don't think so. The reason why is that, the actual game can be beaten in short, but completing every quest in game can take up to 40-50 hours. This is good because you can please both the gamer that wants a long game and short one too.
There is a slight void in between the quests for low-level characters and for high-level characters. It's slightly annoying when you have done all the easy quests and what remains is "Go there. There be raptors."