I want Zoro vs Fujitora, but Fujitora staying with the Navy when all of his actions so far have been what he perceives as right which is usually in contrast to what's expected of him by his job, sounds a bit outrageous. I know it's not confirmed, but Fuji is quite different from Kizaru, he's not a cog in the machine, he actively resists being bent to other people's wills when he can.
Not too long ago, he even fought Aramaki to save some slaves. He was at Dressrosa and witnessed Luffy handling the situation for him and gave him tons of praise, I can't see him put all of that aside to prop up the Navy against the Straw Hats.
Kizaru would be a cool Admiral fight for either Straw Hat, but I suppose once he loses to Luffy, there won't be as much hype for it. Then again, so long as Kizaru remains in the Navy, he's a top-tier opponent that poses a problem. Unless he swaps sides post-Egghead or is removed from the story, he'll still be available to fight later.
I'd enjoy Zoro vs Fujitora and Sanji vs Aramaki, but for Fuji's sake I'm not sure I'd be cool with him remaining with the Navy when everything he's shown prior reinforces the idea he's simply using his standing to do good according to his own beliefs.
I do think both characters are very powerful and would offer great fights. I look forward to them if that's where Oda goes.
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