I don’t think it’s a coincidence if every powerful crew has a captain that is way above everyone else + 3-4 powerful commanders that stand out from the rest of the crew in terms of strength.
- Doflamingo had Vergo, Pica, Trébol and Diamante
- BM has Katakuri, Smoothie, Cracker and Snack
- Kaido has King, Queen and Jack
- Shanks has Ben Beckman, Lucky Roo and Yasopp
- WB had Marco, Jozu, Vista and Ace
- Roger had Oden, Rayleigh and Gaban
Oda did that for a reason. Luffy is about to become a Yonko (literally or figuratively) so it’s only logical that he’ll get his own M3/M4 (Zoro, Sanji, Jinbe and maybe Usopp) with him being on a whole different level.