#2 Sami Zayn

It took Sami Zayn a while to shine on SmackDown Live. He was defeated by the likes of Baron Corbin and Aiden English. However, once he turned heel, he was amazing. Sami Zayn had excellent matches with the likes of Dolph Ziggler, Kevin Owens, AJ Styles, and Randy Orton. Zayn's matches with Randy Orton were the best of Randy Orton's career on SmackDown Live as a face.
He challenged for the WWE Championship multiple times and got pinfall victories of the likes of Randy Orton, Kevin Owens, Baron Corbin, and even current WWE Champion AJ Styles. He was even involved in the angle for Daniel Bryan's in-ring return. When Zayn was moved to Raw, things did not go so well. He did not win a single match and was defeated by the likes of Bobby Lashley, Braun Strowman, and Finn Balor.
Sami Zayn was also involved in one of the worst feuds of the year with Bobby Lashley. Sami Zayn is currently down with a rotator cuff injury. When he returns, it would be best for Sami Zayn to return as a face.
Becky Lynch has been challenged HERE.