4. Shawn Michaels
No rule says the Director of Operations must be at every Raw, Smackdown, and PPV. Back in the heyday of the Attitude Era, there was the authority figure and the WWE Commissioner. With Vince McMahon as a heel, HBK was the man who would come in at the right time to provide justice and make the right decisions.
In the present day, there is The Authority, and there is the Director of Operations. If WWE booked the latter like the former WWF Commissioner role, Shawn Michaels would be an ideal fit. He already used to do the job, and since HBK enjoys the occasional appearance rather than a regular role, this would be an ideal situation for him. Especially when you fact in his ties with Triple H and The Authority.