nope, that new nakama theory was already discuss when kinemon found his foot.
the strawhat's already has two swordman.
that's enough I guess... I believe, Oda's ideas always been unexpected,
so he/she should be different from another characters in Strawhat crew to make their adventures really great and awesome.
what make us still watched/read OP until now? because we're not bored with the characters and their abilities,
if the abilities are same like another, I thought OP can't be the best selling manga.
I think He will be like hachi from fishman island, he will be strawhat pirates nakama but he will not join strawhat pirates but helping luffy and others in the new world show them the way to the samurai island or something
I think he should join, he certainly has that eccentric personality that fits right in with the other Strawhats, something I thought Jimbe lacked.
The real question is about his Son, of course if Oda wants he can make a scenario like he isn't his real son, or this son turns out to be an animal or something. Just saying...
I can see him joining temporary until they reach Wana Country with his son probs.
He might become part of Luffy's alliance like Jinbei for later,but as a crew member i dont see it happening.
I doubt him joining. Though his personality is eccentric. We have seen other eccentric characters in One Piece but they didn't all end up with the SH did they?
As some already said, he might travel with them for a while like vivi. He has to find Momosuke (his son) and get back home somehow. And that's just a lot easier with more people than alone. We are talking about the NW here. And the country has been mentioned often enough to expect an arc there. Especially since there are 2 swordsmen in the crew and one of them wishes to be the best swordsman ever. So it would only be logical that they somehow end up on that island.
They will have some sort of fight there helping out the people and Kinemon & Momosuke will stay there waving the SH goodbye when they embark for a new adventure.