#2 Daniel Bryan
The main explanation for Daniel Bryan not yet sharing a singles match with Brock Lesnar is that he's been retired for most of the last three years, only returning to active competition in the run-up to WrestleMania 34 in April.
Now that he's back, this match has suddenly become one that fans are absolutely desperate to see. Despite their different in-ring styles, Bryan and Lesnar are both excellent workers capable of telling a compelling "monster versus underdog story" inside the squared circle.
Unfortunately, there's little chance that we'll see it this year. At the moment, The Beast Incarnate is very much wedded to Monday Night Raw, with the former SmackDown general manager still over on the blue brand. Perhaps we'll get more luck in 2019.