#4 Jinder Mahal
Jinder Mahal shocked the WWE universe to its very core when he defeated Randy Orton for the WWE championship. A lot of people called it a 'failed experiment' but he has established himself as one of the go-to heels on the roster.
I know Jinder only moved to Smackdown recently, but with there not being that many Baby faces on the Blue Brand, this could be called for.
It looks like Mahal will be going one on one with Bobby Roode at the Royal Rumble for the vacant United States Championship. Although a belt like that suits someone of Mahal's Gimmick is it more than likely they put the gold on Roode to start building him up after a disappointing few months for the 'Glorious One'
The problem is that after this, Jinder would have had rivalries with nearly all the major faces on the Smackdown roster. The easy solution is either make him babyface (which would not suit his character at all) or move him over to Raw for some new feuds, I would go with the latter!