#1 The Rock
As mentioned a little earlier WWE has sort of tried this one before. When Reigns won the Royal Rumble in 2015 the company were clearly expecting some backlash from the fans. That's why they had Roman's cousin, The Rock, ready to go out there and celebrate with him. Famously the plan backfired and fans still booed that year's Rumble winner.
Nevertheless, The Rock is still one of the biggest Superstars WWE has ever produced and is beloved by the fans. It has now been almost a year and a half since we last saw "The People's Champ" in WWE, so whenever he does return he is bound to get a big pop.
How about letting the still disliked Roman Reigns share in that pop? The two could form some sort of Samoan Dynasty team and clean house on Raw during the upcoming WrestleMania season.