I think a John Cena vs. HHH match would be more likely (it wouldn't make sense storyline-wise, but hey!).
If you threw Wyatt and/or Reigns into that, they'd just be there for window dressing, as I don't think either one's really ready to be WWEWHC. And, considering how big these two "young guns" are, why would you put their "crowning moment" on free television when you can build them up to be champ and charge people money to watch it happen? Making Wyatt or Reigns Champion on the Raw the night after Payback would just be a waste.
In fact, crowning anybody in a competitive match on Raw would be a waste (that's as opposed to just handing the title to HHH, Orton, whoever), hence the discussion of having a six-/eight-/however-many-guy-ladder-match at MITB, which makes sense and is "good for business", both in-kayfabe and in-real-life.
Plus, I'm fond of how putting into a "MITB" match (because that's how they'll bill it, I'm sure) for the WWEWHC itself (as opposed to a briefcase....which I'm positive they'll have too.....it's too good a macguffin to be ignored) makes it somewhat reminiscent of the 1992 Royal Rumble, which gave Ric Flair the title (another hint to me that it's highly possible HHH wins the title at MITB, as he models himself so closely on Flair....at least they'll probably promote it that way).
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