My first stab at it:
RB Saquon Barkley, Giants
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RB Nick Chubb, Browns
RB Derrius Guice, Redskins
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RB Rashaad Penny, Seahawks
RB Royce Freeman, Broncos
RB Sony Michel, Patriots
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RB Kerryon Johnson, Lions
RB Ronald Jones, Bucs
I have some thoughts on some of the late round guys, but will keep those to myself for now.
I usually try to stick pretty closely to NFL draft position, so I'm a little bit leery of putting Penny and Michel so low, but neither really wows me in clips. If I didn't know where these guys were drafted, I would not identify those two as better prospects than Chubb or Guice. And since the draft position is still somewhat close, I'll roll with my gut instinct there.
Freeman is an interesting guy because his tape is kind of vanilla, but he's big and he can play all three downs. He could start and rush for 1k+ as a rookie, but at the same time I don't think you're getting a special talent there.
Obviously not a fan of Jones and not totally sold on Johnson. I'd pick Jones as most likely to be a talent bust from this group since he's light, thin, and not very fast. People say Jamaal Charles, but Jamaal Charles can run.