I choose Naruto. My apartmentmate and I discussed this recently. One Piece has character regression in the female characters...and the story lost our interest fast because of how crud the humor is. The story is not clear and it seems like it has no end.

Bleach is close...The characters are the reason why we do not choose Bleach. The characters develop nicely, but then the growing halts. Ichigo STILL does not realize his weaknesses and will not relie on his friends. He is overpowered and very much like a Mary Sue. The women we came to admire are now weak in comparison to the overpowered male characters. We had hope in the character development of Ichigo's friends...but that was halted too.

My vote goes to Naruto because of how all the characters seem to change and develop. Many of the characters that Naruto meet along the way change a lot such as Neji and Gaara. Even Rock Lee changes due to his injury. The main three change a lot. Naruto is very mature now when he used to be a prankster. Sakura used to be a weak cry baby and is now BA and can hold her own. Sasuke was a scoffing nice teammate who became a jerk then he became less of a jerk. The story of Naruto is better than the other two due to how it shows a realistic view on friendships and bonds. I love how Kishimoto shows us very strong women leaders and overall extremely powerful women who do not need men. AND women who are not strong and need men. He gives us a variety of character types making the world of Naruto seem real. That is why I choose Naruto out of the big three.

That's a tough choice, especially deciding between Naruto and Bleach (one piece is more random stories knit together, although really fun, but I prefer anime's with a great, thought-through storyline).

I'll think about it and hopefully come back later with some arguments and a decision! :P