Soo Kaido know about Joy Boy, probably from his Rocks times, wanna know what more the Rocks have discovered about the Void Century, pehaps Xebec even knew about Imu, and that's what he mean by becoming the King of the World, to take Imu place. If Rocks was betrayed by his crew would make sense that when he started to lose against Roger&Garp, BM, Kaido and some others run with the Road Poneglyph, Kaido Fruit and other things, could even be that this things were in God Valley, and after his crew stole this things, they just run away and leave him to fight for himself. Would show why Roger knew that BM have one Road Poneglyph.
High chances of Momo being the Uranus, probably his powers are the thing that are going to save Luffy. Wanna know if this powers are a thing from Momo only, or every head of the Kozuki clan since the Void Century have the potential to awakening this powers, including Oden and Sukiyaki, that would make sense storywise, as that would be the reason why the Kozuki Clan have closed Wano, to protect this power from the WG, and the why Toki have send Momo to 20y, right to the time of the JoyBoy/Luffy. Pehaps this Powers where the thing that the Kozuki used to make Wano like a fortress, could be a power to not only control Zunesha, but the Ancient Giants too, as they have been show to have a connection with Wano, in the OP world itself, and in the plot too, as Oda have been linking Wano and Ancient Giants in the plot a lot of times, in TB he first introce both, them he make a connection of Oars Jr. and Wano via the hats, them in PH he show us Momo and Kinemon for the first time, and put some hints on the Giants, and now in Wano we have failed Ancient Giants, Onigashima Skull and the Wano crazy geology, with pehaps even Kaido, who rules Wano, having ties to the them too. Those two things have been together in the story for a long time.
Really hope that Ashura, Kiku, Kanjuro and Kinemon are all dead, would make for the much needed drama for this arc.