Not trying to make this a swordsman thing (i don't think Kizaru has anything to do with Zoro truly), but I think his power is broken as shit and needs to be handled with Future Sight.
I do have this weird feeling that if Vegapunk gets his own central arc (either alone or Elbaf), Kizaru might serve as the next antagonist for Luffy while every one else handles the SSG/Kuma/Sentoumaru or whomever else exists in the Marine science division.
I think the moment that Zoro/Sanji fight Admirals will be when Luffy fights Akainu and they handle Fuji/Ryokugyuu. Not really a Yonko/Admiral debate, but just think Kizaru's broken power is what serves the upped advantage against Luffy and where I think he might go next.
Plus there's also this:
And the fact that Kizaru had quite a few personal interactions with Luffy during Marineford, I wouldn't be surprised if Oda tried to parallel that shit back at Kizaru by having Luffy kick him in the face.
Idk, probably wrong about this, but I can't shake the feeling that if we need to address Kuma and the Revos, we might be addressing Vegapunk, his SSG and even Sentoumaru and Kizaru. Depends on what comes next, which I clearly can't wait for lol