Originally Posted by Pritha
I know its being selfish but momonosuke doesn't add anything to the group so I don't think he will join SH's
I could go either way on the issue of him joining. On the one hand, asking some little kid, that probably isn't even all that good at fighting, to join you on a epic journey through hell itself where he could die at any moment, is probably one of the dumbest things Luffy could ever do. On the other hand....
...that's basically what Roger did with shanks and buggy. Putting buggy aside, just take a look at shanks. Here we see a kid wielding a sword, that probably wasn't all that strong at the time, and now he's a freaking Yonkou. If this monosuke kid could learn to control his DF power, and add his samurai techs also, he might be a decent supporting character.
I'd be interested to see if chopper could put his medical knowledge to use to see why exactly the DF that kid ate was a dud and if he can come up with an cure to stabilize his powers, or a Rumble Ball that could alter them further.