There used to be a time, pre-ts, when I believed the monster trio would fight one admiral each. Akainu-Luffy, Kizaru-Zoro, Aokiji-Sanji or something like that. Then the ts happened and it became crystal clear that Luffy and Zoro pulled away from Sanji by a fair distance. The admirals are meant to be absolute top tier who very few characters measure up to.
Problem is the time skip has shown that lots of characters are stronger than or at least as strong/on the same level as Sanji.
Characters such as Aladdin, Jinbei, Law, Pica, Vergo, Doflamingo, Cavendish, Bartolomeo, Daifuku, Perospero, Cracker, Smoothie, Katakuri, Ichiji, Niji, Drake, Apoo, Hawkins, Capone Gang Bege, Yamato, Pedro, Inuarashi, Nekomamushi, Ashura Douji, Denjiro, Who's who, Jack, Queen, King, Marco.
Thus a BB-commander it is - the admirals are out of reach and by hype the gorosei as well.