#5 Kenny Omega vs. Brock Lesnar
Perhaps there would be even greater things for Omega to do in a WWE debut. If the company wants to cement a massive new star for it to build around, that road inevitably leads to Brock Lesnar at some point.
This is the program that bedevilled Roman Reigns, and the company's refusal to pull the trigger multiple times cemented his struggles. Seth Rollins is reportedly set to take on the Beast this year, but if Kenny Omega were to show up in the Royal Rumble match, win it, and take on the Beast, it would have an angle everyone would be talking about, which is something Raw is sorely lacking right now.
If Omega were to defeat Lesnar in his WrestleMania debut and bring the Universal Championship back to Raw, it would have a major new star on its hands immediately and prove that its star-making machine isn't perpetually broken.