What tension is there from BBP if they only face the SHs after obtaining the OP? That’s why BBP has to come before that plus the final threat to SHs is the WG and not BB or pirates in general. And no Kizaru and Zoro don’t have unfinished business. And Fuji can do as much as Kizaru does and he is an actual swordsman.
The treasure has nothing to do with the tension from BBPs. Blackbeard's greed knows no bounds, he wont be going after a mere treasure, he will go after the whole world and just like in Marineford, he will make use of the great final war to his advantage and obtain more power. As I have mentioned, Zoro might fight 3 people after he beats Kizaru so admirals being the final threat is far from true, at least in Zoro's case.
But they do, Kizaru was picking on helpless Zoro back on Sabaody, Zoro will pay him back for that, you can count on it.
Fujitora's personality disqualifies him as Zoro's opponent and he cant keep Zoro in check. Kizaru's hax might just be the right thing to keep Zoro occupied. It's not hard to guess Zoro's opponent among the admirals, no need to fight the losing battle. :yasu: