Agreed -- seems like an amalgam. Another possible debate: who is Uhlrich based on? Proto-Sean Parker?
The actor (Christopher Evan Welch) who plays him passed away from cancer this past January. Not sure how much of the show was shot before he died.
Had the same thought about Uhlrich--Sean Parker, but only based on seeing "The Social Network" caricature, with added Mike Judge doofus flair.