It doesn't seem to me as if the crowd is sick of Reigns yet, but I hope they catch on before the Rumble that he's not particularly good. He's awful on the mic, and he only has a few moves, and no variety. He can't carry a 30 minute match, and has no place in the title match at Wrestlemania.
But if Daniel Bryan and Roman Reigns are both in the Rumble at the same time, I think the crowd will turn on Reigns in an instant like they did last year with Batista (and anyone else once it was apparent Bryan wasn't in it). All they could do is eliminate Bryan before Reigns even comes in, and hope for the best. I don't expect either guy will be in the Rumble for too long no matter how they book it, so they better be careful.
In a perfect world, Bryan would win the Rumble and make the big comeback rather than Reigns, but I have no delusions of that at all at this stage.