4 - AJ Styles vs. Braun Strowman

Prior to WWE turning him heel, Braun Strowman had the potential to be the biggest star in the entire company, and if the company were to move him over to SmackDown Live, he'd likely end up replacing AJ Styles as the face of the blue brand.
Even though he's been in the main event scene for quite a while now, Strowman hasn't yet held a World Championship, and as long as he's on the same brand as Roman Reigns, he probably won't get a run with the belt.
Breaking Vince Russo and Jim Cornette update HERE.
Also, Styles is probably the best in-ring wrestler in the entire company, so he could make Braun Strowman look better than almost anyone else on the roster en-route to the "Monster Among Men" winning his first WWE World Title.
One wrong move ended Big E's career - Watch Here!