I guess I'm the only person who wasn't a fan of this character. I liked how he built his entourage, but I absolutely hated him on the mic during this time. He would destroy the gimmick for me when I would see him in a speaking segment, but I will say that I enjoyed the "darker" character when compared to what he was in the E, but I don't like the "AntiChrist of Professional Wrestling" character because Jeff is just too "loveable" to the fans to be taken seriously as that character. However, if Hardy turns heel, I think there is 1 of 2 possibilities that it would result in:
(1) The fans ignore the heel turn and continue cheering him because they love Hardy. This could be used to fully turn Aries face (which is not a good idea to me) but it won't do what TNA is trying to do in creating a Mega-Heel instantaneously since Roode and Bully taking too long to get the true hatred they are looking for (people still respect Roode and Bully too much to give them that Vickie type heat they're looking for)
(2) It turns fans away because they are paying to come cheer for Hardy. If they are made to think he is someone to jeer, they might be turned off by the idea that they want Hardy slapping hands with the crowd and talking to the "Creatures", not trying to look down on them and trying to aggravate them.
I don't think turning Hardy (at least now) will be a positive for TNA from a business stand point. Until people like Aries, Storm, and Styles (I would say Kurt, but his merch sales remain constant regardless of face/heel agenda) are a mega-face that will step into that top Merch sales spot, turning him and risking losing revenue just for the idea of "trying to be creative" doesn't make sense to me.