#1 EC3

EC3 is already a wrestler tailor-made for the main roster. He is good in the ring and is great on the mic.
He's also in tremendous shape in the vein that Vince loves. He crafted his character while away from WWE, helping to carry TNA/Impact through some trying times.
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Since he was able to have such success outside of WWE, it wouldn't be hard to envision him having some success in his second go-around.
He could be a main-event player with his 'Top 1%' gimmick. He can work as a fan favorite or as a condescending heel.
Since he's already tailor-made for Raw or Smackdown, I would think he'd have the fastest track to success on the main roster.
It might be in the mid-card initially but don't be surprised if he's sniffing around the main event level in a year or two.
If he wasn't ready for the main roster than he wouldn't have been among the six call-ups.
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