I think his first priority should be for he and his camp to stop making excuses for why he lost to a better fighter and work on developing some sort of ground game instead of trying to explain away his loss to Koscheck. That being said, I think he should stay at welterweight as long as he can. When he moves up to middleweight he wont have the huge size and strength advantage that he has over most guys at welterweight. He should stay at welterweight while he develops his game and wait to move up until he becomes a little more well rounded. He would get eaten alive by guys like Franklin, Nate, Sonnen, Silva, Okami, Belcher, BIsping, and Hendo (if he comes back). Those guys are all good sized and well rounded.