Most likely candidates have to be Collins (most are expecting him to be a 2-year player), Wheeler (criticized for his TOs and outside shot), Brooks and Toppin (could they take the next step?), Hopkins (the forgotten man of this class who's extremely physical and versatile), and Tshiebwe (might dominate inside far more than we expect if he returns to his freshmen year ceiling).
I don't think many of us will be surprised if TyTy is a star, Allen and Frederick are dependable shooters, Grady is a reliable scorer, Mintz gives us the steadiness he gave us last year but at fewer minutes, or Ware gets lost on the bench.
Of the more likely candidates, I think Hopkins has the most potential to surprise, followed by Collins, Toppin, and Wheeler (if his TOs come way down or his outside shot and/or assists go up). I think because of his physicality and versatility and his ability to hit the outside shot, Hopkins will have more opportunity to play more meaningful minutes than we all think. He's my pick, and even he's under my radar a bit.
As a whole, I expect this team to surprise fans snakebitten by last year, and expect an Elite 8, Final Four level team.