Since Oda đã đưa ý kiến One Piece has only just reached it's climax, we know there's a long way still to go. During that time I think we can expect at least 2 thêm crew members, as Luffy đã đưa ý kiến he wanted 10 of them. Jinbe is almost guaranteed to be the tiếp theo nakama.
Yeah, I think we can expect two thêm crew members in the New World. Obviously we already know that Jinbe will be joining the crew, though not for a while. So, that leaves the crew open for two thêm members to make up the ten... we know Luffy won't change his mind about having ten people in his crew, since he's stubborn.
What I do think, is that the Straw Hats will make thêm allies in the New World.