[spoiler]Buggy was on Whitebeard's crew, which is said to be the closest to discovering One Piece. I believe only Gold Roger's first mate knows at this point, and Luffy told him to keep it to himself.
All the signs are there. Buggy Power-up, plz. He's a lot more graceful already. The Needle Forest was pretty slick.
Buggy is a bit too erratic to follow Luffy, but they're great rivals and counterparts and I think we could go for a pretty "mellow" addition to the crew instead of trying to one-up the outlandish factor. Brook was a fantastic peak! Not to mention Buggy's crew has abandoned him twice now...
I dunno, I just think Buggy could have a total heart of gold transformation and reform slightly. Luffy did show him total trust and kindness, after all! Alternatively, I'm wondering if the Strawhats just take all the Impel Down'd villains to the big Navy/Whitebeard party...
Luffy punches do reform many villains, but Gecko went zombie-insane after losing his living crew. Maybe he mellows out and starts doing his own work.. combine that with Doppleman and I bet he becomes pretty Gemini Man scary. :3c
Feeling kinda meh about Crocodile. As far as personable villains go, he's kind of on the low rung for me. He and Enel are great, but they just don't light me up with a don like Foxie, Buggy, Gecko, etc.
Also I think we're due for Luffy to beat up Jinbei(Whale Shark Fishman Shichi), he was alluded to "starting a riot" at the navy capital and being sent to Impel to cool off.
All in all Oda you rampant stallion of manga[/spoiler]