When OP reaches the final arc in the series, what do you think will happen in it? For one, they'll find One Piece and second, many of the characters (pirates & marines) will probably return but I have an idea in mind,
(Warning: Long post)
The Luffy Pirates reach the island where One Piece is hidden. They decide to find food first. They find some odd but good-eating fruit. Luffy eats it and soon discovers that the fruit is a sort of anti-devil (Angel) fruit and he loses his Rubberman power and is now normal. Nico and Chopper also ate the fruit before learning of what it did to Luffy. The pirates locate the secret cavern where One Piece is hidden and are extremely happy that they found it finally. But then, the marines arrive at the island and launch an attack at the Luffy Pirates. Enemy pirates like Buggy and Alvida also make it to the island and attack. The island is surrounded by pirates and marines. At nightfall, Luffy is found crying by his crew. He's upset that he is no longer a Rubberman that he had loved and feels that without it, there is no use in being the Pirate King anymore. His crew stay by his side and tell him that he is the Pirate King even without the power. By the next day, clashes between the pirates and marines occur. While this goes on, Usopp and Nico figure out that they can use the angel fruit against those with devil's fruit powers. They create Angel Atoms (smoke bombs per say) with the fruit's liquid. The Luffy Pirates battle against Buggy and Alvida and use the Angel Atoms on them. Buggy and Alvida lose their powers. Buggy is then killed in battle against Zoro. Alvida sees that she has become what she once was…a slow, fat woman. She takes her gun and seems to attempt to kill Luffy but instead, commits suicide. The Luffy Pirates next battle against Smoker, Hina and the marines. Nami, Nico and Chopper (back to a regular reindeer) battle against Hina aboard one of the marine ships. The ship suffers an explosion and begins to sink but the battle continues. Nami and Chopper say the battle is over and begin to retreat but Nico stays to battle Hina. Nico tells them to leave the ship without her. Nico uses an Angel Atom against Hina and removes her devil's fruit power. Before the ship disappears below the sea, Hina drops to her knees and cries. Nico makes no attempt to save herself as the water rises up her body and she vanishes below the sea. Back on land, Zoro fights Tashigi. Zoro destroys Tashigi's katana, ending the fight. Tashigi tells that she isn't worth being a swordswoman and demands Zoro to kill her but he refuses. Instead, Zoro helps Tashigi to her feet and some touching feelings and respect are opened and both enemies hug. Tashigi cries and Zoro only sheds a single tear. Usopp and Sanji finish off the rest of the marines as Luffy battles Smoker high up on the island mountain. Luffy is being pounded and beaten but he refuses to surrender. Luffy has only one Angel Atom and throws it at Smoker who uses his smoke powers to blow it over the cliff. The battle intensifies as the marines and Luffy's crew watch on from below. Luffy suffers a serious hit from Smoker and is hurt. Smoker tells Luffy that it's over but Luffy struggles to his feet and charges at Smoker shouting "I'm King of the Pirates!!" and hits him with the Gomu Gomu Pistol. It seems Luffy's will power gave him on last Rubberman attack. Both Smoker and Luffy fall over the cliff and into the sea. No sign of them anywhere. Luffy's crew get aboard the Going Merry and search franticly for Luffy but find no trace of him. Smoker's body is recovered the next morning by the marines but Luffy is still missing. Luffy's crew fear he drowned and hold a small memorial. Another day goes by without any trace of Luffy until Usopp is fishing and something strong tugs at the line. The entire crew grab the rod and pull with all their might and flying out the water is...Luffy! And he is alive. Luffy tells his crew that he sank to the bottom and lost coninous but then he said that Shanks appeared to him and told him never to quit and become King of the Pirates. He awoke underwater and spotted the Going Merry and grabbed the fishing line to be saved. With Luffy back, the Luffy Pirates, along with new crewmember, Tashigi, sail off into the sunset until,
"Um..did we forget something?" Usopp asked.
"We forgot One Piece!! Turn is this ship around damnit!" Nami shouted.
Sucks, doesn't it?