#2 Former WWE Champion Jinder Mahal
Jinder Mahal's first WWE run didn't lead him to achieve much success. He spent much of his time in the comic faction 3MB, and feuded with the likes of Los Matadores, amongst others. Consistently used as fodder for anyone and everyone on the roster, fans didn't hope for a return when he was released from his contract.
However, Mahal indeed returned to the company. His initial gimmick as a Man of Peace was uninspiring, but then he shaped his body to perfection and won the WWE Championship against all expectations. His run was marred by the repetition of the "evil foreigner" trope and lackluster in-ring performances, although he looked and walked like a star, with an excellent theme and entrance.
#1 Former WWE Champion Drew McIntyre
When Vince McMahon introduced Drew McIntyre as a future world champion, fans developed high hopes for him. However, McIntyre's initial promise soon faded and he eventually became part of 3MB.
McIntyre reinvented himself on the independent circuit after his release from the company. He became one of the top stars of Impact Wrestling, ICW and Evolve, amongst other promotions.
He returned and became a dominant NXT star before replicating the success on the main roster. Like 3MB buddy Mahal, McIntyre won the WWE Championship. Unlike Mahal, he has remained one of the company's biggest stars to this day.