Orton is too popular to be a heel imo. His last run as a heel was disastrious whenever he wasn't feuding with Bryan, and since he's consistenly one of the most popular guys on the roster, I feel they should keep it that way. I'd love to see him feud with Bray Wyatt, Kevin Owens, etc. He doesn't have to be a heel to feud with Brock Lesnar, as we're currently seeing with Brock/Ambrose. Brock is the closest thing we have to a tweener.
He dropped Heyman with one in October of '14. Ironically, it marked the only time that I can remember where Lesnar didn't take action against someone for assaulting or offending Heyman.
Also if Jericho can pull of being heel then so can Orton. They have similar careers