User blog comment:Fintin/How Many More?/@comment-81.205.255.186-20100622042430

Boa and Jimbei won't become part of the crew. Boa has her island and Shichibukai status to maintain, which she can use to help Luffy. Jimbei will probably need to defend fishmen island now Whitebeard is no more.

Luffy was always very vocal about which roles he wanted on his ship. A cook, a navigator, a musician, etc. I think he filled all the roles he wanted on his ship. So if there is another crewmember, it would be by luck. But let's have the gang get themselves back together first, ok? That could take a small year worth of chapters by itself.