If we're going by intellect, Nami would foil Marco AND Ben. As a matter of fact, Nami and Ben were canonically the top three smartest people in the East Blue. Chopper could also parallel Marco because both are doctors.
Where do you get that Rayleigh's a perv like Sanji? Because he womanizes? If we're going by that logic, then Rayleigh has more in common with Brook (both fight with swords and Brook is even worse than Sanji in that department) than Sanji.
Roux would make it 1 of 4 at best? You mean the guy who fought Zoro and whose flashback where he meets Kaido was juxtaposed to Zoro meeting Luffy is the one who parallels Sanji? Not the guy who has history with Germa 66 and starves people, and was Sanji's actual opponent?
That the BB Pirates could be their last major battles. Luffy could still fight Imu right after, and even then, I'm not entirely sure on that.