While I strongly believe Yamato has made his presence known and now people are considering him as a candidate for nakama, I still stubbornly believe its going to be Carrot. People think she's gonna be a captain of a fleet which makes no sense when she lacks seniority or authority over anyone to listen to her and she's been way to invested in the Straw Hats journey as a random tag-a-long. I genuinely don't see her simply going away.
I think the possibility is that it could be:
- at its lowest: just Jinbe
- at the middleground: Jinbe and Carrot or Yamato
- at the best: All 3
People are mostly calling the parallels between Yamato and Oden right now, in that Oden was waiting for a powerful pirate to take him away from Wano. Yamato almost seems to be carrying that will from Oden with the same exact dialogue to Luffy. I agree that we need to wait, there is so much we don't know.
On Carrots end, it still just is a matter of if she is going to do something signficant this arc. Like Yamato "possibly" carrying Oden's will, Carrot is 100% inheriting Pedro's will, a man who did not have his chance to join Roger to the end.
This is why at the moment I'm somewhat confident in Jinbe, Carrot, and Yamato having a triple join ceremony. It's interesting that Oda even drew a whole scene where Luffy postponed Jinbe's celebration. It could be because he wants everyone to join together on their different circumstances.
Just keep an eye out for these 3 this arc (well, Jinbe is secure at least lol)