Gotta say, I have no idea where we're really heading for Mania. I'm not sure that's a good thing.
Only two matches really feel set in stone. Gunther vs Jey Uso, and Charlotte vs Tiffany Straton. Aside from that... who knows.
HHH's style is kind of like reality TV. There is simmering tension between... well almost everyone. You could make a case at Mania for Cody vs Punk, Cody vs Cena, Cody vs Roman, Cody vs the Rock, Logan Paul vs Cena, Logan Paul vs AJ Styles, Bron Breaker vs Seamus, Breaker vs Logan Paul, Rollins vs Cody, etc.
Whether that's a good thing or not... eh I dunno. It's kind of fun to still be guessing at this point, but I also kind of want to have something to really sink my teeth into. Last year's Mania also had a strange build, and it all came together nicely, so we'll see if there's a method to the madness.
My current prediction is that we'll see CM Punk vs Cena vs Cody, and Bianca Belair vs Rhea with maybe Iyo Sky in the picture.