WWE Hall Of Famer Edge was no doubt one of the best heels when he was an active Superstar in the company. He definitely has knowledge of what it takes to be a great heel.
He recently spoke on Out of Character, where Edge criticized modern day pro wrestlers for not portraying heel characters well. He stated that heels nowadays are too overpowering.
At some point, there needs to be that heel that is not the overpowering heel. That is the conniving, that is the manipulating, that is the ‘Oh man if the babyface could get his hands on that guy he would tear him apart.’ But he never gets him because the heel is always two steps ahead. I don’t know who that is right now, or who’s being given that opportunity, to be honest. Somewhere along the way, it became less about heels and faces and just about stars. But in that, I think you lost some of that dynamic.”
h/t to Wrestling Inc for the transcription.