Having to be a fan since 2004, One Piece appears to be less and less appealing to me and there are several reasons for that. Please no flaming and bashing. This is just my opinion.
- Timeskip: Ever since the Timeskip you'll think the characters would change but it appears that some characters have not changed. Like Chopper's gullibleness or Nami's short-tenderness or Usopp's crowardness. Oda appears to keep Nami, Chopper, and Brook a weak trio and almost never get enough spotlight.
- Lack of real adventures: In Magi, characters would explore dungeons and around the world dealing with empires, One Piece almost have no adventures since Skypiea and would never explore dungeons. The current arc is hardly an adventure. The Straw Hat Pirates have to disguise themselves, they always gets chased by Marines, they go visit islands that has cities and not an empty plains dotted with ruins and strange creatures.
Adding regional race that turns out to be a work of a Devil Fruit: Centaurs and Styers turns out to be a work of an Ope-Ope no Mi, meanwhile in Dressrosa the toys are the result of the Hobi-Hobi no Mi. One would wonder why Oda can't just add natural races in One Piece. I would not be surprise that once we reach Big Mom, she wo uld be surrounded by bunch of living candies and it was revealed to be result of someone who ate a Candy-Candy no Mi. Oda loves to limit things to a Devil Fruit.
One Piece is still cartoonish and goofy: Last time One Piece was dark and serious was in Water Seven. After that One Piece fall into being overly goofy. One Piece sometimes have a mess up rules like Usopp falling from the tower of Enies Lobby and is still alive but injured but in Thriller Bark as Zoro was falling from an tall heights it was stated that he will die from that fall.
Lack of different powers: Haki and Devil Fruits, Sword Techniques, and Material Arts is getting boring. Would it be neat to see Ninja skills, Chakras, Magic in One Piece?
Lazy Naming: One Piece is riddled with this. Its like Oda was staring at the paper of an character and said "I think I'll name him Killer".
One Piece: We been kept in the dark about the treasure and the Void Century for 15 years and we still don't know what its suppose to look like and what it is.
But One Piece is still interesting and still has some appealing qualities but I wish One Piece would open itself some more and knock it off of those silly names for each characters and bring in some real adventures