#2 Big E

Big E has been an important part of New Day. He has been enjoying a great run along with Kofi Kingston, who is the current WWE Champion. There is no denying that Big E has played a pivotal role in Kingston's rise to the top of the ladder.
Big E made his main roster debut as a heel when he was the bodyguard of AJ Lee and Dolph Ziggler. Subsequently, he achieved plenty of success after winning the Tag Team Titles five times. Despite having a huge potential, he never got an opportunity to become a big singles star.
A heel turn could be highly beneficial for Big E if WWE wants to push him as a singles star. Following the rise of Kofi Kingston, WWE could propel the former NXT Champion. It will not be surprising if Big E turns on the New Day. Considering Big E had an association with Ziggler in the past, the former could join the hands of the latter. The company could book a blockbuster match between Big E and Kofi Kingston at Summerslam.