#4 Lars Sullivan
WWE has traditionally been known as the land of the giants, and the 'Freak' fits right into this world. Lars Sullivan is a superstar with a look that is imposing, if not downright terrifying, and should fare better on the main roster than he did in NXT for the same reason. We've been seeing vignettes of his arrival for many weeks now, and each of the videos has been scarier than the one before it.
During his time in NXT, Sullivan would attack his tag team partners and was portrayed as a man with a temper problem that he could not control. He would channel this rage and become a heel monster, taking the fight to the resident babyfaces of NXT. At the peak of his popularity, he challenged NXT Champion Aleister Black at NXT TakeOver: Chicago II.
He's destined for great things in WWE, because of his imposing build. He can also work, albeit not at the same level as the independent talents that come to NXT.