A litttle bit? He's Luffy with pink hair.
Well see, Nami and Lucy love their outfits and greedy for money, both are loose about what they wear, both hit the main lead because of their stupidity, both act like their in control of the gang except for the lead female characters(Robin and Erza). Luffy and Natsu? Obvious, both are extremely slow in the head, hot headed, impatient, loud, immature, and love laughing like retarRAB. Aside from there themes there practically parrellel twins.
LOL really? replace rubber with fire magic and you get One Piece GT.
Luffy gets as mad and hotheaded as well, he holRAB grudges, he yells at people, he acts before he thinks. The same when their in a bad mood. I say Happy and Ussop carry the comic relief. Well your right about that one. But still it's fairly more similarites with the two manga's then differences.
Naruto > Fairy Tail.