Oh god how I'll love if the overarching Rocks plotline continues till the end of the series. The biggest thing holding it back is how Oda will portray the typical country liberation part of the arc without Kaido getting defeated. In fact there are many more like-
Oden's claim on how the protagonists of future will defeat him which is kinda lining up neatly now, the question of opening Wano's borders and it would feel awkward if the scabbards' endeavors and struggles were only for Kaido live through this arc lol.
The other side of me thinks how it would be weird if Big Mom would potentially get 3 arcs dedicated to her and Kaido, who I would argue is built up to be the bigger villain in new world perishes in Wano.
His character arc seems to have been barely scratched the surface and I'm not even touching upon other aspects like his demonic lineage or him potentially being a dragon.
In my opinion there's an overarching lore surrounding dragons involving the presence of literal dragons in the past, Kaido and Yamato potentially being dragons, celestial "dragons" -their obsession with having them as pets and using their hoof as their symbol. To some extent I would say Monkey D Dragon ironically having that name can be added to that list too. The bottom line is that Oda wants to explore more of this and Kaido could be a central figure in this later