i personally prefer robin, but i havn't seen the entire series... toonami only got about 1/3 of the way through the skypea arc... therefore, i don't know how many other girls there are in the series.........
I, myself would prefer Robin. Hancock, too. I just despise Nami. She's an arrogant bitch like almost every other heroine in an anime/manga. Except for Chidori Kaname. She's a bitch, but you know she likes Sousuke. And it can be pretty cute sometimes. Her bitchy side, I mean.