It's amazing how people are still clinging to hope that Paulie will join. To paraphrase Bill Hicks, it's a commitment I cannot relate to.
Seeing as this discussion should be based upon all of the water 7/Enies Lobby arcs, it'll be one giant spoiler for the recent chapters. Noobs proceed with caution. ♡
! This all seems rather moot, since Paulie is possibly dead. Oh, and if anyone would like to say that Oda never kills people, I'm afraid I'll have to cut you off. Has anyone forgotten Bellamy? His head's been lopped off, if I remember correctly. {chapter 303 page 7-8}
! The following argument consists of conclusions I have reached on a basis of the facts presented, rather than illogical preference. (That is, "DUR HUR FRANKY/PAULIE IZ JOINING CUZ HE'S MY FAVORITE AND THUS COOLER." No. That would imply that I have control over Oda, our lord and master, or that Oda's work bows to the subjective whims of fans. XD)
! I am using the MSN One Piece Manga group as reference to the following evidence.
! ★ Franky was on the Colorspread, verbally and visually grouped with the Straw Hat crew.
! ★ Franky is on the cover of volume 43
! ★ Franky has no reason to return to Water 7
! ☆ He has no home to return to, the Franky house was destroyed. {Chapter 330 page 17-18} And though he could possibly build another one, he would have no reason to, because he's too well known now, for the acts in the following points.
! ☆ He destroyed the Pluton plans. {Chapter 399 page 12} The World government will either want to destroy him or capture him to torture the plans out of him, (if he does indeed have them memorized.)
! ☆ Franky has not yet been told that Iceburg still lives. (He was told that Iceburg died. {Chapter 352 Page 13}) And should he discover that Iceburg is indeed alive, it is my firm belief that they have no more to say to each other. Their past is now simply that, their past. Their relationship as brothers cannot return to how it was
! ☆ Zanbai, as second in command/Leading Bro/What have you, has been consistently set up to take over the Franky Family with the Square Sisters. {Chapters 366-390, 399-425, too many pages to enumerate.}
! ☆ Luffy entrusted Franky with Robin's life. {Chapter 418 Page 18} I cannot emphasize enough how this should not be taken lightly. Also, note Luffy's serious smile when he says "It's all up to Franky now, to take care of Robin!" {Chapter 419 page 3}
! ☆ Franky's dialogue against Spandam. {Chapter 423 Pages 6-12} (Please note, some extraneous dialogue, only consisting of "haah," sound effects or marine's speaking has been omitted) Bolded for the comments pertinent to my argument.
! Spandam: Hand over Nico Robin and I'll let you off the hook! Why do you bother protecting her, anyway? It's not like you're a pirate or whatever!
Lemme get this straight, you'd rather side with those pirates and the demon woman of Ohara… than side with the protecting, everloving World Government?! If you do go against us, you and Tom will- Punched out by
Franky
! Spandam thoughtbubbles: This is getting annoying! Hey, Funkfreed! Stop Nico Robin already! Knock her out!
! Spandam: TAKE THIS! Elephant Chop!
! Franky: You really are…
Spandam: What!?
! Franky: a hopeless fool.
! Spandam: Funkfreed! Why are you loosing to him?!
! Franky: Yo, elephant, morph your trunk back, unless you want some bullets in your head.
! Spandam: WHAT ARE YOU DOIN? KILL 'EM ALREADY!
! Franky Ah, that's a good boy… Nico Robin, Are the strawhats gonna come here?
! Robin: Yes, definately!
! Franky: I've already told you that my life is on their lines, Spanda!
! Spandam: Uh… What?!
! Franky: I never thought this day would finally come... If I could've fought that day...
Brief Flashback, Kokoro: Just remember this, boys! Your lives were saved by Tom! you'd never survive against those folks! Even if you were immortal!
Cutty Flam: STOP THE SEA TRAIN!
! Franky: I always wanted to save Tom, no matter what! Even though we all fear Enies lobby… And the power of the world government... The strawhats decided to challenge that authority! They challenged the world, just to get their friend back! That makes me look up to them a lot! I've never forgotten about Tom's death! And every time I saw that bastard Spanda's face... I've always wanted to rip his throat out!
Spandam: Whoa! Hey, stop it already!
! Franky: JUST LIKE THIS! Thanks to the straw hats, I was finally able to do that! Weapons left! I've already stared into the face of death once before! I don't mind doing it again for the strawhats!
! Franky was previously unable to get his vengeance on Spandam. He has accomplished this thanks to the strawhats. Chopper was previously unable to avenge Hirurulk and take the path towards becoming the greatest doctor. Sanji had simply remained on the Baratie. Usopp still had yet to even leave his home island. Nami was previously unable to be free of Arlong. Zoro was simply wandering around, getting bounties and half-assedly looking for Mihawk. They all needed a catalyst to resolve what stood in their way, which Luffy or the Straw hat crew provided. Thanks to Luffy, they can all follow their dream now, helping him follow his in the process.
! I'm not even directly referencing all the bonding between Franky to Robin, Chopper, Usopp and Sanji, compared to Paulie fighting solely with the Franky Family.
! Paulie may be interesting to a number of people, however the lack of requirements to join the crew is too plain to ignore. Paulie has no dream, no history, no significant character development and no reason NOT to return to Water7, should he even live from the Buster Call.
To be short, no. No hope at all. :)