Do you really aspect Oda to make 3 characters of a crew of 10/11 (moreover a one of them is a cook) Yonko/Admiral fighters level? That has been the peak of the manga for more than 20 years, it would feel cheap. For Luffy and Zoro it's necessary for realize their dream so he can't draw back. Sanji will learn how to active the exoscheleton at will like Zoro will learn how to use Enma better, after that Sanji will stop, there are no others possible power-ups, Zoro will turn Enma black and surpass Oden, Luffy will awaken his devil fruit. It's clear where the manga is going, it's not needed a genius to understand it, Luffy and Zoro have dormants power-ups remaining, Sanji no.
first of all that pseudo-argument should be discarded., sanji being the cook does not imply a damn thing
Marco is a doctor and he's strong as hell.
at this point in the manga the dream of the characters is irrelevant, oden had the dream of opening wano and going out to sea, and he was infernally strong, to the point of making kaido his dog even dead.
Shiro had a dream of having a family, yes, a family and ended up being one of the two strongest legendary characters in the verse.
and so there are more examples, so no, that he is a cook or that his dream is not intrinsically related to strength has absolutely nothing to do with his final power
Now then, you say his level would be at the rank of first commander? how is that? Sanji will stop fighting? did he lose his legs or will he separate from the band?
I tell you because unless sanji dies in the next chapter, sanji will continue to grow.
Sanji is currently a first commander with ease. Even if you're a sanji hater, you should at least admit that he's a YC1 because of the way he beat queen, even if you don't want to give him that, that's fine, yc2 sounds good.
so far ok? all the muguis progress passively (between arcs) and actively (fighting), even more so the monster trio.
Sanji improved his armament haki, said by himself, the germa genes improved his other physical stats.
and the haki flourishes with the hard battles, it is fair to say that sanji's weapon haki grew more in his battle against queen, and will continue to grow in his next future battles, that as I emphasize to you, unless sanji dies, it will continue to increase in Power and strength.
like it or not, sanji will be there, in the top league