Here's what I said yesterday in other thread about it.
If pushed to make an absolute decision, I'd say it's Zoro vs King and Marco as a main fighter against Kaido. But I do feel it can go either way right now
Really him and Zoro are in the same position. One of them is fighting King, one of them is fighting Kaido. Nobody else makes sense for them. And there might be a bit of crossover to boot.
For both of them, Big Mom's out because she has nothing to do with their conflicts in the arc. Marco is here to avenge his crewmate, who was killed by Kaido and the Beast Pirates. Zoro is fighting for the people of Wano who've been oppressed by Orochi. Orochi is incapable as a fighter, so his fight will have to be against the people who have made his regime possible- again, Kaido and the Beast Pirates. Big Mom has nothing to do with these crimes, and as such is not a suitable opponent to them considering their story in the arc.
Yamato is the wildcard, but my gut instinct is he is not a foe to be defeated.
The lower Calamities aren't opponents with enough narrative oomph. We're talking about the right hand man of the future Pirate King, and the right hand man of the uncrowned Pirate King. For Marco it's quite basic- he's simply assumed to be capable of beating Queen and Jack, so it's not really that interesting. Zoro's still growing, and while we could say that Q and J would be a real fight for him, it isn't how Oda really does things. He'll want to match the right hands with the right hands- it's no coincidence that the team charging at Kaido right now is Luffy, Zoro, Kid and Killer.
For both of them, Big Mom's out because she has nothing to do with their conflicts in the arc. Marco is here to avenge his crewmate, who was killed by Kaido and the Beast Pirates. Zoro is fighting for the people of Wano who've been oppressed by Orochi. Orochi is incapable as a fighter, so his fight will have to be against the people who have made his regime possible- again, Kaido and the Beast Pirates. Big Mom has nothing to do with these crimes, and as such is not a suitable opponent to them considering their story in the arc.
Yamato is the wildcard, but my gut instinct is he is not a foe to be defeated.
The lower Calamities aren't opponents with enough narrative oomph. We're talking about the right hand man of the future Pirate King, and the right hand man of the uncrowned Pirate King. For Marco it's quite basic- he's simply assumed to be capable of beating Queen and Jack, so it's not really that interesting. Zoro's still growing, and while we could say that Q and J would be a real fight for him, it isn't how Oda really does things. He'll want to match the right hands with the right hands- it's no coincidence that the team charging at Kaido right now is Luffy, Zoro, Kid and Killer.
If pushed to make an absolute decision, I'd say it's Zoro vs King and Marco as a main fighter against Kaido. But I do feel it can go either way right now