How would you imagine each member of the Strawhats' new battle techniques that is distinct and unique from their existing skills?
Like Enies Lobby arc, where each gain their superior skills that made us go WOW! (e.g. Gear Second and Third, Diable Jambe)
I have given some thought about it but could not come up with a lot of new creative skills, save for Brook. I would give Brook the power of summoning, where he can summon for the Reaper to deliver a serious near-death blow with his scythe onto his opponent (most likely to be a finishing blow). Or perhaps summon Hades to drag an opponent or a group of enemies' soul for a tour into the Underworld, upon returning back from there, the tourists will be greatly demoralized from fighting. I was thinking of being able to summon Cerberus to fight for him but since the Cerberus has appeared in Blackbeard's Jolly Roger, I passed on that idea.
A not-so-creative thought is to have Nami evolve into becoming more like X-men's Storm. Do away with her rod / staff, she will own a scientifically created gloves which depending on how she move or touch her fingers, she will activate certain weather elements (e.g. lightning, tornado).
Franky may become more and more like a Transformer. When facing a giant, he will merge himself with his vehicles to become a huge robot (something like Voltron or Dino Power Rangers) that stands almost a tall (if not taller) than Monster Chopper.
Robin may develop like how user Shinjojin imagined. If you have yet seen, you should take a look at the works done on Robin by the user. Though that would have change Robin into a more proactive melee fighter than she currently is now.
What makes Usopp unique is his use of a slingshot (not bows or guns) and pellets of various abilities. I would be disappointed if he is to switch to conventional weaponery (bows and arrows or guns and bullets). Therefore I could not foresee how his next battle development will be.
As for the monster trio and Chopper, I have no idea how would they develop at the next level.
Have you any creative thoughts? Do share below. Have a good weekend.
What say you if Doflamingo were to "fall for good" in the Dressrosa arc? "Fall for good" means his role in One Piece will end permanently.