Re: One Piece 661
Let's not forget bio feed back.
Both Luffy and Zoro have been shown to be able to use it. Luffy by instantly converting all the food he ate at IP into energy, and Zoro when using his Ichi/ni gorilla attack.
Lucci was able to change the ratio of his transformation with it as well. He had a bulky hybrid form for power and slim one for speed. Those could be explored later.
I do envision Luffy's improvements being more strictly physical from here on out. Better speed, strength and durability/endurance. He should also get better at hand to hand combat, even though he is pretty good at it already. Special move wise, red hawk gatling, jet elephant gun, basically gear stacking.