there are quite a few wrestlers as of late that i have been very impressed with not just by wins but technique, mic skills, and overall getting over with the fans. a few of my picks for future champs and why they would work:
SWAGGER: this kid is amazing, one of the few actual wrestlers WWE has on their roster, he has great mic skills, brash, arrogant, and can back it up - he needs a few high profile wins over some more mid carders and in a few months have him (believably) score a win over HHH or cena
MVP: again great mic skills, another cocky technician, raw is shooting for a PG rating to appeal to younger crowds why not push the "i grew up making bad decisions now i've turned my life around" gimmick...let him feud with swagger
ZIGGLER: he is impressive, has the look of a champ (way more so than his spirit squad days) and has had a very successful push as of late, continue with the cockiness, the underhanded wins, and the opportunistic heel moves...and we could be seeing a slightly different Edge in the future
MORRISON: first of all i would love to see a tough enough contestant actually go somewhere, secondly, he emits charisma very similar to the earlier days of HBK, and jericho, work a bit on the whole palace of wisodm shaman of sexy thing and he could and probably will become huge
finally:
KANE: for god sakes the man has been with WWE forever now and had only 1 title reign which lasted 24 hours, kane has the ability if done properly to become that sadistic psycho character and pushed as a monster heel then have the savior (be it Cena, HHH, edge, whoever) come in culminating into a huge feud that sees Kane rightfully hold that belt for a few months at least