I regret to inform you that I would no longer be working on One Piece Shippuden. My reason for this is that I am working on another big project One Piece: Final Holy War which is also a Luffy defection fic. One Piece Final Holy War is a huge fic and would be one of the longest One Piece fics. Right now it is not even half way done.
Having said that I wish to say that One Piece: Shippuden is up for adoption. Anyone that wants to continue it feel free to do so. Just PM me and we'll take it from there.
As for anyone who likes the Luffy leaving plot, here are some ideas that I have been brainstorming:
During Rogers execution, the corpse of Roger was stolen by Dragon, the Gorosei, whatever. This person used Roger's corpse to create a clone of Roger to use as their ultimate weapon. This clone of Roger is none other than Luffy.
Every person has some kind of evil. Be it small it is there. For Ussop his evil lies in his little perversion, for Sanji it his in his huge perversion. For Nami, it is in here greed for money. But what is Luffy's evil. His evil is in the form of a split personality.
Ace's death has resulted in Luffy gaining a split personality which is the complete opposite of Luffy. This personality comes after a certain incident say, someone badmouthing Ace or his crew faces a powerful and unstoppable foe.
Luffy finally squares off against Akainu. But just as Akainu is about to kill him, Dragon arrives and drives Akainu off. He then asks Luffy to leave the crew in order to train him and make him stronger.
Luffy has a twin brother. This twin brother grew up under Dragon and the revolutionary army. However Luffy's twin brother is the polar opposite of Luffy. Cold, calculating and evil. Furthermore he is too extreme even for Dragon. Furthermore Dragon is suffering from the same disease as Roger and is on his death bed. And asks Luffy to leave the crew so that he may train Luffy. Luffy's mission, kill his twin brother and prevent him from destroying everything. It doesn't have to be Luffy's brother it could be any revolutionary extremist.
There are many strange things in the New World. Luffy however stumbles upon a portal that is linked to a parallel world, one devastated by war. Luffy is trapped in there to endure the horrors of war. When the crew finally get him out, they find that Luffy is not only older but hardened and no longer the same Luffy.
The Ds are actually descendants of the sea devil, the creator of the devil fruits. The sea devil has found its host, its descendant Monkey D Luffy. Using Luffy as a vessel, the sea devil starts its conquest to destroy the world.
The sea devil blesses the world with the devil fruits. However people like the world government and pirates uses the power that the sea devil gave them to enslave others. The sea devil decides that mankind should be punished for it's crimes of misusing the power it gave them. The sea devil posses or convinces Luffy to help with this goal.
The world government, Dragon or some other powerful figure completely overwhelms Luffy. Furthermore this fic threaten's his crew. The only way that figure would leave Luffy's crew alone is if, he joins them.
Haki is a common power in the New World. What if there is a second type of haki, dark haki. This haki manifests itself in only certain circumstances such as during times of great rage or sorrow. What if this haki suddenly took over Luffy.
Shanks's/Garp's death at Blackbeard's or Akainu's hand pushes Luffy over the edge. First his brother, then his grandfather or friend. Leaving the crew, he hunts down Blackbeard, gaining power while loosing himself.
These are just some ideas that some of you can use. Feel free to use them. You can change them around to suit your story as you see fit. You can even have a fic where Luffy joins the revolutionary army however One Piece Final Holy War is my story.
Again if someone wants to adopt Shippuden, PM me. And if you want to use some of the ideas above for your own fics, feel free to do so. I hope to keep you all entertained with One Piece Final Holy War