Rey Mysterio vs Daniel Bryan - WWE Championship
Daniel Bryan is on fire as WWE Champion right now, and the WWE should do all that they can to keep him looking strong into WrestleMania 35.
While a rematch between Bryan and Styles could certainly be on the cards, it would be nice to see Styles spend some time in the Rumble this year, and it would also be refreshing to see somebody else involved in the WWE title picture. Also, another defeat at the hands of Daniel Bryan doesn't exactly do him any favours.
Instead, Bryan could just flat out refuse to give Styles another match, arguing that he beat him fair and square and that Styles shouldn't be so entitled. It would enrage the fanbase and really establish Bryan as the top heel in the WWE.
Given the lack of faces on SmackDown right now and the fact that the only other real competitor for Bryan, Jeff Hardy, is wrapped up in a feud with Samoa Joe, Rey Mysterio is the best option for number 1 contender.
They could always make this a triple threat with Randy Orton, given that he and Mysterio have been involved in a feud as of late, but given that Mysterio defeated him at TLC, it makes sense for him to step up for a match with Bryan at the Rumble.