Well. I see several problems. For example the anime stretching situations too much. Like Kaido charging his boro breath for a minute. Or Luffy in the sumo tournament almost falling off the edge for like a minute. And other countless moments of stretching a situation.
Also, some scenes have little to do with the cabin manga. The thunder Bagua being different in the anime compared to the manga, where Kaido charges at you. Thinks like characters turning into a light flash while attacking, Luffy using a KKG against Kaido, etc. It's much shit imo.