If One Piece immediately went into those kinds of arcs right away I'd drop One Piece. Look at what happened to Naruto, Bleach, Reborn, Fairy Tail. They delved into epic arcs too early, and after the initial high everyone lost interest in it.
I hope you'd take a Literature class in the future and learn how a story is made, since what you're saying is a misconception that must be fixed.
Nah, I don't think Naruto has matured.
Mmm, I have some issues with this.
1. The 100 chapter transition arcs from Oda may be repetitive and unoriginal, but so far it's worked for 13+ years and counting. No need to change something that works like they say.
2. The most interesting fight Luffy had was against Lucci. Lucci was the first person who could keep up with Luffy physically and not rely on weird powers. They were equal in a sense, and if Lucci had the sense to use Kami-e instead of tanking the Jet Gatling, Robin would be captured by now. So I say Luffy's most interesting opponents are the ones who match him blow by blow.
3. I don't want plot advantages anymore. Well I know there will be some, but not something blatant like Dragonforce or Son Goku and Kurama. I've had enough of those to last me this year.