who do you think he will face
Well, Queen looks like someone on who Sanji can knock himself out IF he doesnt fight with swords which could be possible as he didnt resort to them against Big Mom.
He could help Luffy against Big Mom as they have already that mutual panel against her in WCI, perhaps Sanjino with his best could do some damage to her. I dont expect anything significant since I expect Queen his major fight but could help to some degree vs BM.
He could chime in against Kaido BUT do you expect him to put a scratch on him? ...
Those bullets were specially made to bypass the suits.
Well, are those bullets superior to swordsmen who possibly can cut through Kaido's scales?
I dont put much weight on the flying. Many have been able to fly and still fought on the ground.
All Sanji, Zoro and Luffy have defeated opponents who can fly while they weren't able to...
I find it unlikely that Sanji fights King since I think the suit is of no help there while the suit may be the perfect counter against Queen's plague. Another thing, the plague makes people burn from the inside and that is perhaps exactly the trigger that Sanji needs. He burned on TB by himself. We taught it was a gag scene but maybe not.