#2 Kevin Owens
Kevin Owens' rivalry with the McMahons has been the high point of 2017. The headbutt to Mr. McMahon was talked about around the world, and even Shane McMahon couldn't beat Owens at Hell In a Cell. The only one who can redeem the embarrassment is 'The Cerebral Assasin', Triple H.
While Owens and Sami Zayn are still "fired" from WWE, a possible angle could have both of them move to Monday Night Raw after WrestleMania. This gives WWE the perfect opportunity to have him feud with The Game. A high-profile rivalry with Owens retiring Triple H will be best for business.
Kevin Owens is the true successor to Triple H. The last pure heel in WWE, KO is a prizefighter, who has never backed down from a fight, just like HHH. The Prizefighter is just 34, which likely means that he is the future of WWE and will be featured in the main-event scene for years to come. Ending the career of someone like Triple H will be a great boost to his career.