I agree with a lot of what lucky said beyond "boom or bust".
None of these guys are busts. Marvin Williams might be invisible, but he's shown himself to be a viable piece on a very good team. He's not an elite player, but he's an okay option on team with 3 potential 20pt scorers.
Gordon, an established scorer. Can't knock it. Hibbert...meh. He's a starting caliber center.
Wall is as "can't miss" a prospect as this year's draft had to offer. When you factor in the success of recent pg's with his physical skills, Wall is a pretty safe bet to be an elite PG in a few years.
Jefferson to me doesn't have much to prove on the offensive side of the ball. He only has to prove that he can defend, and he can learn how to win.
So boom or bust I don't see. None of these guys can bust, with the unlikely exception of Wall.
The team might not win initially, but they'll be given years to figure out if they boom or bust.