If Katakuri scaled to top tiers (assuming like, a similar value to Queen or King), and was in Wano, how do y'all think the rooftop would have changed?
Assuming he actually made it to the rooftop unlike the rest of Big Mom's crew-
If he showed up in Wano and had trained or something, I imagine he would start out as sort of an enemy figure. However, he would block King's attack, telling him they were here to help, and win an audience with Kaidou, but Big Mom would probably still get lost.
Basically, he would open by following Big Mom around and looking for her. Meeting her, he'd pretend to be a wandering drifter when he realized she had amnesia. The Straw Hats with her wouldn't make her attack him, since he was a clear threat to them, and could kill them both before she hit him. When he did, he would see Queen attacking her and help her beat the shit out of him, with Big Mom killing the Beast Pirate.
Seeing her in this more innocent form earlier, he would kind of wish she had stayed like that. However, he would go around, shooting out any prison guards that jumped him. Luffy would leap out at him, and they'd clash. Luffy would go G4, and Katakuri would be outmatched by his superior power and Haki. However, Big Mom would interrupt the fight, knocking Luffy into a wall, then doing the same to Hyougoro when he tried to stop her. Then, Katakuri would hit her head with a Buso Mochi hammer, and she would fall unconscious. Finding some Seastone chains, he'd wrap her up and take her home. This wasn't their time to fight. Luffy had promised he'd come back and fight his mother someday.
When the group showed up back on Whole Cake, Germa wouldn't be a big issue. However, Aokiji and Van Augur would. Big Mom could beat Aokiji, and Katakuri the same for Van Augur, and they would be forced to retreat without Pudding.
Meanwhile, with the Raid, Perospero and Big Mom wouldn't be there, and Queen would be dead.
This means:
-The Straw Hats would take down a few Numbers easily
-Marco, Wanda, and Carrot would make it in uninjured.
-No one would be stalled in the Ice Oni area, except for everyone beating down on Apoo.
-Chopper would be free to heal anyone he needed to.
-Nekomamushi and Inuarashi would fight Jack together with the other Minks.
-Marco would fight King one on one, and most likely defeat him, considering the allies around him.
-Kaidou would stand through Roof Piece alone, with Sanji now there as well, and would be defeated after a series of battles where everyone awakened their powers, except for Luffy not having G5.
The Straw Hats would go on with Luffy not having G5. When he faced Rob Lucci, it would be much harder, but he would win. When he fought Kizaru, he would be killed, and come back in his changed form after Sanji and Jinbe stalled Kizaru for a bit.