Cody Rhodes wasn't a top heel when he was "Dashing", he was an average run of the mill heel. Once he became disfigured at the hands of Mysterio, then he began prospering. To say the moment Legacy split was the moment Rhodes became instant entertainment is absurd, WWE were using Ted DiBiase more after Legacy than Rhodes for the better part of half a year. They removed his gimmick, gave him a mask and all of a sudden, Cody Rhodes began shining.
I wasn't all that over Rhodes when he was undashing, for lack of a better term. He overplayed a lot of things and his promos weren't all that great. More he got into it, the better he became. Rhodes won me over when he was feuding with Rey, the more we progressed into 2011 the more I began taking a like to him. He improved greatly, when he dropped the mask he became a generic heel but something simple personas are the most effective.
Is he the best thing on Smackdown now? HA! Not a chance, hes been entangled in a mid-card feud with Big Show for the past two months over the IC Champion, he hasn't been putting on a show to the calibure of Daniel Bryan, Randy Orton, Kane or Sheamus; and Sheamus hasn't been all that great. I'm sure if they give him a new feud he'll rise again into prominence on the Smackdown brand, but he isn't currently the best thing about the show and with Christian's eminent return, he'll only fall further down the pecking order.