#4 AJ Styles vs. The Miz
The Miz, for a long time, has held the reputation of being an "average" worker. I feel that's simply not true. Miz is not the kind of person to elevate an opponent (unlike, say, Styles or Seth Rollins), but when he is placed with world-class talents, he absolutely steps up. Just look at his match against Rollins at Backlash, the Fatal Four Way at Extreme Rules in 2016, and many others.
Styles and Miz have faced each other before (I believe Miz was one of Styles' first feuds in WWE), but that was before Miz became one of the greatest heels in the company. They had another match on SmackDown in 2016, but both men were heels, and it didn't last very long.
Miz's return to the main event scene is long overdue. With Styles as the champion and Miz on a hot streak, they could put on an amazing match for the WWE Championship.