heres the thing abt kairi. i don't think she's poorly written, i think she's poorly executed. like there's a conflict/lack of cohesive vision for her and they're trying to shoehorn her into a role she does not fit.
I agree with some points except the fact Kairi having a keyblade isn't really a shoehorn in plot.
From concept Kairi, Riku and Sora were all original gonna have their own keyblade. Do I think Nomura doesn't really put much thought into yes but I think that stems from the fact her role changed from how she was in concept. From her being a after thought in alot of the games. But that doesn't mean he doesn't have plans for her. Especially with taking into account the interviews. One interview he stated there's more to explain with Destiny Embrace and more.
This is coming from a soriku shipper (who personally think Soriku has a chance of being endgame) but Kairi as character despite representing the childhood friend that you slowly drift apart from does have a role. After all she does end up causing events whether she ment to or not.
Her showing up on the islands being one of those. Or the fact she and Riku together are the only reason Sora was able to walk around the final world the way he does.
My personally theory is Kairi is there to but a guiding light to follow in the light sorta like Master Ava. While Riku is the light within the dark. Kairi clearly does have alot we don't know about her and I do think Nomura does plan to address it at somepoint but just she isn't the main focus of the series like Sora and Riku doesn't really make her character progression inconsistent. I generally just think people try to say she's a main character when she's more likely than not in a position that Ventus, Terra, Xion and for argument sake Aqua is in where she's a character that will get developed but doesn't have to be in the fore front.
But that might just be my opinion. Also the fact that we still don't know alot about Namine (who is able to create dark corridors, many memories and is referred to as a witch) Kairi some how and some form gonna be developing or related to that based of Namine being her nobody.
Especially if you interact with the little ponds in kh2 they say they've been used but who were they used for before Sora Donald and Goofy and why was Namine able to have access to them.
Namine and Kairi both are stuck in mystery. Like for some weird reason. The fact Riku gives Kairi her keyblade who's to say Namine didn't summon it first kh2 we don't get to see her after Riku let's her and Axel escape there's also the fact in kh2 Kairi is reference to escape Axel twice before getting caught by Axel. (Not saying she spawned her Keyblade) but the fact we don't know alot about both characters seems like Nomura just planing to either use them later.
There's also other things in interviews that Nomura has stated about Kairi if I find them I can send them but I don't think she's gonna just always be stuck representing the childhood friend. (I personally hope we get a side game cause I liked her combat where she's learn self worth cause she compares herself to both Riku and Sora to much wanting to catch up.)
Also want to make this clear I don't mean this to come off as attacking you. Just wanted to point out somethings that you might not have considered.
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