I'm honestly warming up to the idea that Marco, Kid and Inu/Neko take on the All-Stars
I only say this because that is exactly what happened with Dressroasa, it serviced the plot. Kyros got revenge on Diamante. Law took out one of the executives (who arguably was closest to Doflamingo, save for Vergo, whom he also beat) being a personal achievement, and Zoro trumping an executive as well. Franky and Usopp took out lower level people, along with a wide variety of SHF members taking on the rest.
The same could be said here. There are only like 10 Strawhats to 30+ villains. Inu/Neko vs. Jack is clearly set up like Diamante vs. Kyros. Kid vs. Queen would give Kid the edge he needs to keep up with Luffy, and it also services the plot to get revenge as well. Marco vs. King would be pure fanservice.
I'm in the boat that if Luffy doesn't solo Kaido (which is very unlikely given the amount of people that are poised to fight him), I'm not sure how or why his top 3 would solo Yonko commanders.
BUT, I do think Who's Who, Sasaki and maybe Drake are viable replacements, being "around" those levels of the All-Stars.
It's the same reasons why I can see Izo/Kiku facing off against Smoothie/Campote/Amande or something, or why Law may fight Snack, or Asura could fight Perospero, Killer vs. Daifuku, Robin/Shinobu/Raizo vs Fukurokuju. Not for sure choices, but possible guess to who people could actually fight in the end.
We'll see how it goes, but there are many upper tier characters on the good side, not just Zoro, Sanji and Jinbe, whom have the ability to grow well past this arc. Would you want them to be Yonko commander level characters before they fight Blackbeard's or possibly Shanks' top commanders? It's the same reason why I don't expect Luffy to solo Kaido, hell, I don't expect him to really win at this point in the story.
Edit: Hell, these guys are very likely going to fight the Admirals while Luffy takes on Akainu. Let's remember that they have to grow. 3 Tobi Roppo captains are big acheivements too.