I just read a One Piece ending prediction in Korean and I think this one is the best prediction so far. I translated into English as best as I can.
(This post is more interesting when you listen One Piece OST :Three Towers)
(link to the music)
Straw hat Luffy entered the new world.
He got very famous after his enterence.
Zoro fought against Mihawk and he finally defeats him.
When the Straw hat's crew reached the finalisland Raftel,Robin deciphers ponegrif and they find out what is the "One Piece"
One Piece = One ocean
However, the four oceans (East Blue, West Blue, South Blue, North Blue)
are separated by the Red Line.In order to find the One Piece, Luffy must destroy the Red Line. An ancient weapon Pluton was built for this purpose.
Former pirate king, Gol D. Roger tired to destroy the Red Line with Pluton.
However, the Marines and his illness interfered his dream.
The straw hat pirates goes to war against the Marines. The three admirals were extremely strong, however, Aokiji, who wanted to make the true peace
by rejoining the four ocean, betrayed the marines and joined the Straw hat's plan.
He also has a debt from Jaguar D Saul and Monkey D Garp.
Luffy finally defeats the marins and he used the rioponegrif to activate pluton and he finally destroys the Red Line. After the Red Line is destroyed, the 4 oceans became one. The One Piece.
Since there were no boundaries between the 4 oceans, all kinds of fish can live in one ocean.
That is the All Blue Sanji wanted to find.
And one whale that lives in the All Blue, the whale that Brook had met 50 years ago…..
Luffy finally gets the title of the Pirate King. However, after his success, he turns himself in to the marines.
Luffy was weaken by intensive stress from his Gear 2nd and 3rd.
The Marines schedules an execution at the town where Roger was executed.
People who were saved and helped by Luffy came to the execution to save him.
However, Coby, Smoker, helmeppo and ironically, Luffy's crew members stops them.
Later on Coby and Helmeppo become admirals.
After his death, the pirate era ended and the world is no longer in chaos.
One Piece = One Ocean = One Peace
This prediction is made by a South Korean student (grade 9)
Original text link (Korean) :