#2 Appearance by The Rock
Believe it or not, an appearance by The Rock could actually help Roman Reigns this time.
Sure, it absolutely backfired back on the road to WrestleMania 31, when The Rock returned to congratulate his cousin on his Royal Rumble victory, but that was mainly due to the way WWE treated Daniel Bryan during the Rumble match. With that being said and Bryan now permanently on the shelf, WWE would be smart to go back to this idea and implement it
For example, what if WWE put a biased referee in the match between Lesnar and Reigns like Paul Heyman? Not only would doing so be an interesting way to stack the odds against Reigns and create reasonable doubt about him winning, it also allows for a timely ref bump later in the match, which WWE can then use to allow The Rock to make the save.
Imagine The Rock's music hitting and him running down the ramp in order to count the pin and help his cousin win the Universal Title for the first time in his career. In the end, some Roman Reigns haters won't be happy with how this match plays out regardless, but this could still be a great way to get a positive reaction from some fans!