I think Chambers is the best despite the size disadvantage he over the other rising prospects. Pretty good crop of talent I say.
Povetkin beat Chambers and you can see something in Chambers that is amiss, mentally. Until Povetkin is beaten he is the best of this bunch and has accomplished the most. His resume is very strong for the limited amount of fights he has had. Povetkin aslo seems to have the will to win. I for one am excited to see where he goes next.
A lot of boxing fans still wonder how Chambers drop the ball when he lost to Povetkin, because he was in control the first four rounds. Although I agree with you Povetkin is the best prospect when it comes to rankings, in the near future though I don't think he will be. I can see him losing to Dimitrenko, Botsyov, Arreola, and Chambers in a rematch.