#3 Should: CM Punk
CM Punk chants are still audible in a lot of arenas. Though the man has expressed his disdain for the company, anything can happen in the WWE. Fans have clamoured for his return ever since he lost to Mickey Gall, in his debut UFC match, mounting a very little offence. Many started believing that Punk belonged to the WWE and performing for UFC would only damage his legacy as a pro-wrestler.
The man who had an immense impact on the WWE, including the longest modern day WWE championship reign of 434 days, would be welcomed by the fans with open arms. He still has a lot of gas left in the tank. His presence is definitely going to help WWE boost its numbers and let him realize his dream - main eventing Wrestlemania.