Kid's "yonko crew" is just going to be a combination of the remaining supernova crews. Bonney, Urouge, and Capone aren't relevant enough by themselves to really make a difference in things going forward. The only way these characters can be relevant is if they team up with stronger, more relevant characters.
I think Kid makes the most sense, as he is a conqueror and will probably force these guys into submission if he sees them. The way I see it:
Kid= emperor
Killer= YC1
Urouge=YC2
Capone=YC3
Bonney=YC4
I'm not entirely sure Kid will be crowned an emperor. At this point, it honestly seems unlikely to me. I think Luffy is going to destroy the emperor system altogether, with Luffy, Kid, and Law all being dubbed "legendary pirates" like Roger, WB, and Shiki.