Alright, the canon is already start when mr.3 appear and he'll meet the strawhats next chapter.

For the power level i'll make a list of comparison from Naruto's shinobi world and Strawhats power. I'll make their power level a little similar so it will be easier. Even tough i think Narutoverse's peak power is higher than One Piece coz there're tailed beasts and Otsutsuki but to reach that power they need a lot of time, there's no way MC can reach that level in just 2-5 years after he come to one piece, he's just an ordinary guy before.

Even Madara and hashirama reach their level after decades of improvement. Even if he's reincarnated there's no way he'll become that strong in a short time, he's just gonna improve really fast but not instant. I try to make this believable alright. Maybe he'll become that strong when he's at Dragon's age, but not while he follow Luffy to be a pirate king. I'll make him strong but not stronger than his captain and maybe about Zoro's strength. But i'll try to make it entertaining and i'll change some part of canon, pls wait fot it.

Anyway, this is the power comparison:

-Luffy at the beginning of journey = Special Jonin near Jonin

-Luffy at grandline (paradise) = Jonin

-Luffy at Marineford = Elite Jonin

-Zoro after time-skip = Low-Kage (idk who's stronger, Luffy or Zoro but i'll make Luffy the strongest of strawhats, he's the captain alright)

-Luffy after time-skip = Middle-Kage (i make him skip Low-Kage because he became very strong after being trained by Rayleigh)

-Admiral = High-Kage

-Yonkou = Super-Kage