Why can't he just go away?
BLASPHEMY!!!! Shawn is the only man that can superkick Chuck Norris and Norris feel it!
In all seriousness though, I would lean more towards him being the GM.
I've said before that if you were to take the "And I quote"'s from Cole and read the emails in Hunter's voice, it could so be him. HBK and Trips are pretty interchangeable as far as their smart ass remarks on the stick go, so I could see this being more plausible than him being a ref.
I doubt he'd phrase things as "future with WWE" if it were a one night gig. Anyone who follows Shawn on twitter knows he doesn't mix words.
As for the talk about comparing him to Flair or Hogan - it's totally different. Flair needed the cash and Hogan...well...after his marriage fell apart and his kids sort of pushed him away, it was Hogan who needed the spotlight to feel important, loved, needed, relevant, etc.
HBK doesn't NEED the spotlight, but Vince knows he NEEDS HBK in the spotlight to get the ratings back up. They (WWE) lost too many established stars due to "free agency", injuries, and retirements over the last year.
Shawn won't get back in the ring, he has said that over and over and over on twitter, but him working the stick as the GM would be stupid sweet. Like someone else mentioned, he did the "Commish" thing after he hurt his back. And the cat works the stick like no one else in the business today (notice I said IN THE BUSINESS TODAY, because Austin owns the stick and the Rock leased it out) and could definitely do wonders for teaching the next generation how to do it the way he did.
Back to the GM role...picture this...The Miz and A-Ri are in the ring and talking mad shit. HBK comes down in a nice purple and black suit (ahem, check avatar, ahem) and tells the Miz what time it is. Mi runs his mouth...CRACK! A little sweet chin music, then a straightening of the tie and a reconfirmation that Miz will do whatever it is HBK told him he would do. Yeah...I'd mark out for that like a mother fucker.