I'm still pretty new on One Piece so please forgive me if my list seems off
6.Boa Hancock (Her sexiness makes her DF ability OP unless of course you're gay like Luffy)/Jinbei
1.Monkey D. Garp (I have an extreme bias for Garp)
No disrespect towards Aojiki I like him alot but I personally think the others are better.
To be honest I don't even fully agree with my list. My knowledge on One Piece isn't eh best so it's harder for me to to a ranking list for OP than it is for Naruto especially since the power differences in Naruto are much more clear (probably due to the story reaching it's climax), so I completely understand if anyone decides to bash my list