the characters! really, it's hard to create so many great characters and make them so lovable .. even the evil guys are just awesome! and oda doesn't just throw "old" characters away .. nooo~ he brings them back ^-^ either with their own cover story or as a part of the current story and this .. is amazing!
furthermore, the interaction between the characters! i've never read a story with this kind of family feeling the crew shares. and i've never read or watched a story where i liked every main character .. i just love them, and by the way oda portrays them, how could you not? i also love the developement of every one of them .. the background info, etc.
and a great character doesn't have to be eye candy. most stories chose good looking characters coz it's more appealing to the audience .. not one piece! yeah not everyone is butt ugly .. ^^'' but usopp is one of the best characters and he's .. well .. not exactly what you call eye candy hihi ^-^
you know, 10 years ago i read loads of mangas .. things chance and i grew up .. i stopped reading mangas .. except for one piece. and from time to time i start reading other mangas which sound promising but after a few chapters .. they start to get boring .. -__- .. they either have romance :sick: .. training arcs … dumb characters .. or the worst .. all three of them ..