I do think that the current rating system is needlessly finegrained (there's basically 100 different ratings possible) and making it hard to really attach a common value to a rating. I'm personally in favor of a simpler system, with five stars or something, or even a binary "useful" vs "not useful" rating for, for example, utilities. The big problem is obviously that there's thousands of uploads using the current system and having two separate rating systems on one site isn't a very good idea.