Imo, I don't think all characters (generally speaking-regarding KH or otherwise) strictly "need" development. Character Development is "a character changing throughout the story". It really depends on what's trying to be accomplished with the characters that determines whether or not they even need significant character development, or any at all. E.g., we're told from the very beginning that Sora isn't a person who changes much, which has resulted in him getting little development. Which I'm fine with because for starters, we're already told what kind of person he is. Second, a good chunk of the stories resolution depends on him being a certain way.
Sora is a character I take is supposed to be "idealized". Rather than growing with him as the story progresses, we, the audience, are supposed to admire or even aspire to be like him on some level. On the other hand, we have Riku who has he most development in the series, but I take it that he's supposed to stand in contrast to Sora. He's the overtly flawed character that we're supposed to sympathize with.
With that said, I think some characters are fine in the ways of development, while others definitely need some work. All things considering, most of the characters are relatively simple and just need some good characterization.
I guess that boils down again to the issue of seeing "character development" and characterization/screentime as interchangeable terms when they're in fact mean something different.
I realize that I also tend to tap into that trap occassionally, lol.
On Sora I think you're completely on the mark and all those fans who cry for Sora to get more "mature" in terms that he has to get darker and more gritty have not really understood what Sora is supposed to stand for.
Yea, but in order to even get characterization they need to be
involved and shown first, which is something the series seems to have a problem with as well as most characters who could profit from it are either trapped somewhere (be it Sora's heart, Xehanort, the RoD or whatever) or left dangling in the background (Kairi being the most offensive example, but there is also the danger that in KH III, everything done by characters other than Sora, Donald and Goofy will again just take place as background events with very few or no coverage, just like II already did).
Definitely agree with these posts. Riku and Lea, at least, have had more than enough characterization over the series that they can serve more as characters that aid in the development of other characters rather than needing additional development.
Most of the original characters have either had little to no characterization (Kairi, Namine, Isa/Saix, Luxord), but I also kind of wished that there was more development for other that have little. I'd like to see more of how the Disney and Square Enix characters react to the events of the main plot more.
Xehanort too though, he's practically all over the place and despite some remaining mysteries which have to do more with the people he possessed rather than himself, we have a very clear view of his motivations, actions and views on matters.
Indeed, after Riku, Lea and Xehanort I think Roxas comes second in terms of characterization, followed by Xion. The BBS trio had some rudiments in BBS, but all in all the game fell short of the true potential they had in order to flesh out TAV (which is why I certainly and fervently hope that those aren't just "saved" in KH III in order to serve as sacrifices yet again).
Naminé had some decent characterization in CoM that extended partly into KH 2, but the latter was, much like Days, only scraps of something that could have been fleshed out better.
Sora sort of stands outside the list, mainly because he's the main protagonist anyways and everything either directly or indirectly revolves around him and Ruran already explained his "lack" of development.
Isa/Saix is an interesting case as he continued to grow more important as the series went on, yet most we know of his characterization stems either from other characters (Axel/Lea, Xemnas, Xigbar) or from outside situations.
Most of the Disney and Square characters already have established characterizations from other sources though, unlike the originals who have
only the KH verse itself, so this may not be that big of an issue, especially when considering that the Square/FF characters are nothing but cameos too.