There was this one game or book… I forget the name... where at the end, after everything was resolved and the world was right again, the main character simply vanished. The characters just woke up and noticed he was gone.
That's kind of how I want One Piece to end. The strawhats just wake up one day to find Luffy missing, and they search around and find a note that says:
"So long, my nakama. Thanks for everything."
- Monkey D(Whateverdstandsforwillfinallybewritten) Luffy.
Then everyone will wonder where the hell he went, and it will flash to Twin Capes lighthouse.
We'll see Luffy yell for Laboon, and Laboon will apear.
Luffy will look up at him and say, "I said I would be back, didn't I?"
Then he'll throw a punch and the series will end before the punch connects.
Either that, or the same type of deal, minus the note. That way, everyone can wonder, "Was it all a dream?"
Btw, people DO die in One Piece. Stop trying to beat a dead horse.