Lol, anyone who sets their favorite character to be 'their' arc, are only setting themselves up for disappointment. Unlike fanboys, Oda isn't obliged to give x amount of spotlight to a straw hat. He does as he see how the story fits. The only person who we can expect to have spotlight for every arc is Luffy, cause he is the main character. In Wano right now, we already have the Supernovas, with people like Kidd and Law. So that only means less screen time for the other straw hats, including sanji and zoro.
A lot of people took the 'Year of Sanji' bait back in WCI, promising he'd 1v1 Katakuri. Yet, we didn't get much more than a flashback and a cake baking. I'd probably expect more or less the same for zoro. Probably even less for Zoro since I still don't think Oda's gonna have Wano to be 'Zoro's arc.' Yes Wano is the country of samurai and swordsman, but its also much than that. The only things I expect from zoro are a good fight, and MAYBE, zoro recreating the feats of Ryruma by using his new sword Enma to be able to scar and cut Kaido, just like how Oden did. That would be a pretty big feat for Zoro alone, to be able to scar a yonko, and Kaido the beast no less.
As for 1v1 fights, of course I want zoro to get a good fight and opponent, cause out of the Monster Trio, Zoro still hasn't really gone all out yet. The fights he had in the new world up till now have all been either skirmishes or one shots and low diffs. Because of that we still haven't seen zoro's true strength post time skip. As for his opponents, previously Kiroshiro was my choice, but now he's an ally so that's too bad. My next choice would be King since he also wields a katana. However, given how few strong fighters we have seen from Kaido's crew so far, the 3 calamities might be reserved for other more important characters like Luffy and the other supernovas for example, that's IF Oda doesn't have all 3 of them team up on kaido.
We really need to see more prominent members of kaido's crew before we can come up with better matchups. Cause right now other than the 3 calamities, the rest of kaido's crew don't offer much for 1v1 ones, so much of the crew is filled with fodder and mooks. Headliners like and Hawkins is also no longer an option, since he joined kaido with no choice, its almost certain he will switch sides to the alliance. Drake is an undercover marine. That just leaves us with the likes of Apoo and Page One etc. We really need to see more veteran and high tier fighters from Kaido's crew ( the 'Numbers' maybe?), and hopefully soon too.
There is also the option that maybe zoro can 1v1 Smoothie, now that Big Mon and Kaido are in an alliance. The Big Mom pirates who aren't already defeated (Katakuri, Cracker, Snack etc.) are still up for grabs and available for fights. I'd also like to see more of Daifuku and his genie too. But it's still early to tell if it will happen.