Some Sanji fans are just coping, they just want to have a cool opponent for Sanji as well as an aerial fight.
Most of Sanji's opponents are either goofy in design or have a goofy personality or even both.
It's not that I'm against Sanji fighting Laffite or even Mars, if he fights them then awesome, but I know that isn't going to happen.
I think the only cool opponent Sanji might maybe fight later on and that's a big maybe is Crocodile.