The only potential Reigns has is as heel, kinda like when Edge was turned because as rebellious babyface he got booed all the time. The thing is Edge spent over a year after he turned feuding in very heated personal stuff, before even attacking Cena.
Also, by that point, Cena was already getting stale to the fans, so they were glad there was a new heel to piss on him. The same Cena who got over also because he got against JBL, one of the worst WWE champions of all time a la ADR. Much like Batista got over as he went against Hunter "somebody please stop him before I drink a whole bottle of bleach" Hearst Helmsley.
Why would anybody want Reigns to defeat the big bad Barack Lesnar? The heat he got from beating Undertaker was squashed by Heyman the night after WM30. Right now hqe's as over as most upper midcard babyfaces, he's pretty much a tweener.
The problem with WWE is that they never, ever consider the reasons for a feud. It's hardly ever
personal. Ambrose is the guy who for months went after the guy who stabbed them in the back, and he's midcard for life.
Roman Reigns is this years Batista.
Not even close, like really.
Batista had a better dragon to slay, way better reasons to do it, let alone reasons to do it period.
EDIT: Oh, you mean because of the reaction? Any guy who wasn't Bryan-Ziggler-Ambrose would get smashed like he did.