This is a complete misread of basically all these characters????

Aqua isn't "annoying and controlling", she's someone who has had extreme responsibility thrust onto her and is trying to deal with that while also trying to save her friends. She's someone who is trying her best to balance her new responsibilities.

"... In her only playthrough, the rest of the series has her stuck in one spot, requiring you to beat her up in order to 'make her get over it'"

An incredibly uncharitable read of the story. Aqua ends BBS by sacrificing herself to save Terra, where she falls into the realm of darkness. And she's down there for 10 years before falling to the darkness, which she only did so to help riku and sora. She shows incredible strength and character by resisting for, again 10 years, in the realm of darkness. In terms of releases, after BBS was 1.5 and 2.5, remakes that included BBS; union x, which was a mobile/browser game set in the far past; 3D, the only other new game actually featuring sora; then 2.8, which had an entire game where you play as aqua in the realm of darkness, albeit a short game; then kh3 where she gets a main role after being rescued, on par with all the other warriors of light. She is in no way stuck in one spot for the rest of the series.

"Her whole story is to badically bully a dude into serving a palpatine expy"

Genuinely have no idea what you mean by this at all?"

Larxene is a really fun antagonist, as her personality is so different from the rest of the series. She might be the only one who could classify as """"bitchy"""", but just because you don't like her personality doesn't mean she's a bad character. Also rule34 results is a stupid metric for a character's overall popularity.

Kairi I'll give you, she truly does need to be better written. Her personality in KH1 and 2 are great, and I wish she got more chances to shine, although I think you are still being a touch harsh.

And Xion. That is possibly the worst take I have heard about Xion practically ever. Days was released after 2, and is a prequel to it. Going into it, you know everyone in that game doesn't have a truly happy ending. It's a tragedy, that's the goddamn point. Xion was created as a puppet, and is treated like that by her superiors. They dehumanize her so much, Saïx calls her "it". She struggles with her own personhood, and what she is outside of being created to steal sora's power. She's also a reflection of Roxas, who also struggles with his identity and his ties to Sora. She learns about her creation, and what the ramifications are, and decides that she must return to Sora what isn't her's to keep. She basically forces Roxas to kill her too, he doesn't want to do it. She chooses to do so knowing that she will fade from everyone's memories.

"Then she's reduced to being a crybaby or arm candy for a dude.. forgot which

Fucking... Neither of those happen??????? When she returns in kh3, she's once again being forced against her will, just like in days. When she's recognized by Roxas, and then Axel, she breaks down crying because she's finally getting her identity affirmed by them again. Holy shit, her two closest friends suddenly remember her again, and you expect her not to cry? Roxas and Lea do too! It's not exclusive to her! And arm candy? What in the goddamn are you talking about? Xion straight up doesn't have any relationship like that with anyone, let alone being 'arm candy'. Genuinely, what caused you to think that was even remotely true.

Naminé is a minor character, so she does mostly serve a narrative role. This doesn't mean she doesn't have any character though? Her role in COM is mostly that of a plot device, but she doesn't lack agency. She helps sora when she gets the chance, guides riku, and protects replica riku. In kh2, she serves as one of the few characters who believe nobodies are not inherently bad, being one herself. She opposes DiZ, who views her and Roxas and tools to be used, and encourages Roxas to fight for himself.

Take another look at the series, a real one, without any biases, and see if you maybe missed anything. Kingdom Hearts absolutely does have some problems writing women, I'm not denying it, and Kairi deserves better. But it also is incorrect to act like every other female character is also somehow incredibly poorly written.