#2. Cody
Due to the unprecedented success of All In, you might think Cody has little motivation to work for WWE again, but there are several things to consider.
Firstly, while All In was a big success, it was not something nearly as grand as a Wrestlemania. Wrestlers are performers, and while their craft is important to them there's no sensation quite like performing in front of a massive arena full of cheering fans.
Second, yes All In made Cody money, but not as much as you might expect. The Over Budget battle royal was an in-joke that even if the show were a success--which it obviously was--there would be a reduced profit on the part of Cody and the Young Bucks. Cody could still make more money working for WWE with the right contract.
Third, a lot of Cody's friends still wrestle for WWE. Despite his warm feelings toward the Elite, returning to WWE would be like a homecoming for him.
What he would bring to the table for WWE: Cody is not only one of the best technical wrestlers working today, he's parlayed his creativity and charisma to gain massive stardom. He could put that brain to work for WWE both inside and outside the ring.