@andre:
The deepest layer of One Piece is just a boy going to sea to become a great pirate, have a crew, and find a treasure left behind by the greatest pirate to ever live. the story absolutely could have happened without any of the characters if Oda wrote it that way, but they all are vital to where we are now. I really don't agree that Nami and Zoro's as the devil/warrior and angel/logician on Luffy's shoulders are any more vital than anything else. Everything after Luffy deciding to go on his voyage is a specific choice Oda has made about what is vital for this crew. And remember, he originally thought he could complete it in 5 years! Every current crew member was planned from the start to resonate in this story. I would argue that Sanji and Brook particularly are just as important to the story Oda is telling than Nami and Usopp. Again, what use is an adventure without good food and music?
What's important to realise is that there's an hierarchy of importance between all those elements in order to make the story function.
I'm not saying that the "lesser" Strawhats don't add anything at all. Of course they do. But that they're way less essential to the raw dynamics and themes of the story.
What does Nami add to the story that Usopp, Sanji, or Chopper couldn't if she was gone outside of her role as navigator?
As I said, the character can be technically replaced, but at the end of the day there's someone who the author chose to play that role.
What Nami does as an "angel/logician" to Luffy is something that 90% of the time it is Nami who does it, even if other Strawhats were intellectually able to do it. That's because a story is artificial and characters are assigned dynamic roles on a thematic level. And that's one of the main reasons why Nami have so much screentime every single arc since her role is so big. And that's why if there's an important dillema inside the crew, you'll probably see Oda giving more focus to Nami and Zoro than the others.
Luffy had been talking about the need for a musician from the very beginning. Literally chapter 7, even before Nami was introduced.These are vital positions to Luffy's personal adventure.
Ornamental.
Koby's role is literally the role you're saying that Smoker is going toward. He's already there. If anything, he makes the idea of Smoker becoming a Straw Hat because of this redundant. Working together with the young buck and the old legend to reform the Marines seems more on point, in my estimation, and all of them are equally as important. Even though there are small differences, they're all telling the same story, the one against Absolute Justice. It's not a coincidence that Garp was both Roger's biggest adversary and is still alive!
Definitely not.
Coby was the first person Luffy met in his journey to make a contrast between their personality in order to show Luffy as a role model to his young readers, because Luffy is Oda's "ideal child". While Luffy had boundless determination to achieve his dreams, Coby was full of insecurities, fears and a restraining mindset. "Impossible, impossible, impossible", Coby used to say.
However, through Luffy's influence Coby decided to seek his dream and give it his all. That's the influence that Oda wants Luffy to have in his young readers too. So when Coby becomes an admiral, it is to say that anyone can achieve big things as long as they pursue it wholeheartedly, even if they weren't born with the same nature as Luffy.
So that's Coby's character conflict and concept. Obviously, since he's in the marines and the marines are about to becomes villains, Coby will also have to face this issue… but that's not central to the character.
Smoker is another beast completely, a character who was built from the beginning as someone who was chasing Luffy because "pirates are pirates", which is the black and white ideology that rules the world... and ever since Alabasta Smoker is learning that justice actually can come from a pirate, something that he is very reluctant to fully admit because that's his character conflict, still unfinished.
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@Deicide:
I'm one that believes that any story can be fixed, and thus Carrot (or anyone else) can get whatever it's lacking to flesh their story and be elevated to main character status.
My problem with it is finding that if that's really what the author's intentions are. Carrot so far is fine for a secondary character, and given that this is One Piece, secondary characters are often really well-built. I don't see the author wanting to go beyond that with her, thought.
The answer, of course, is to wait and see. But, right now, given what was presented to us, Carrot is another Kin'emon or a lesser Law: a long-standing companion that has a purpose within the story and her own arc, but is not meant to permanently be with the main cast.
That's totally fine, and you might be right.
The difference between everybody here is that each one of us had a different impression of the weight of her scenes, which is largely based on the different ways that each person reads a story.
