Hell No.
To me every heel that is main event status needs to be a face first and have a long run with the world heavyweight championship. Then when the fans least expect it you turn and thats what makes a good heel
Punk in ROH was brilliant as a heel and was great to watch and he will be if he turns heel in WWE but at the moment it is not the right time. The fans still need to put all there "Trust" Into punk until he should turn heel. He is currently world champion and until he gets stale then there is no need for a heel turn. He gets ratings for Raw! and has held the title extrmely well.
He is great to watch as a face and if the turn him heel Raw! will go back down in ratings to were it was 2 months ago which is were they do not want to go.