As has been mentioned:
Seth facing either Ambrose (this would have to be some kind of a stipulation match, but Ambrose would need to go over) or Orton with Seth losing to open the show would be the best match, leaving him open to cash in on the winner of the WWEWHC match later in the night, which he should win (of course, I don't think a cash-in should ever fail, just like I don't think a cash-in should ever be "scheduled"....I'm looking at you, Cena).
If it's Bryan who wins the title and gets cashed in on, which seems like it would make the most sense, that sets up a hell of a feud between Rollins and Bryan over the title. If it's Reigns, it sets up a good feud but I don't think the matches will be of the same quality. Of course, I look at match-ups between Rollins and Bryan the same way I look at match-ups between Steamboat and Flair or Sting and Flair back in the NWA/JCP/WCW days: it's always going to be a good match and it's always going to be entertaining.
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