#1 The Roman Reigns anti-thesis
Before I go any further, it should be cleared that had Brand Split been a thing anymore, most of these things wouldn’t have been possible. Joe is now a RAW Superstar whereas Reigns is, on paper, on the main roster of SmackDown.
However, since everyone is literally allowed to go anywhere now, WWE could use it to their favour and have Joe pit up against Roman Reigns in an all-out good vs evil feud, where the former could promise Reigns that he is going to bring the worst out of him by the time it all ends.
It would be an incredible story with a lot of psychological factors where Joe goes to insane lengths to break Reigns. This could end two ways: Reigns wins the title but Joe succeeds in bringing the worst out of him (winning the psychological war in the process) or having Reigns have complete victory where Joe fails to bring out the darkness.
The ending is up for the company to decide but it could really push Reigns and Joe as the two faces of the company.