I've noticed with SoKai it's really just how Sora acts in the scenes that makes the whole thing feel off. Now I'm headcanoning that he and Kairi were romantically in love at first, however Sora's feelings changed after their reunion at The World That Never Was but he's afraid of hurting her feelings so puts up a facade.
^ But heck, even as a boy Sora and Riku's scenes ooze romance.
They even made beautiful music together~
Granted things always turn out okay. Nobody dies in Kingdom Hearts after all. XD Though come to think of it, that mentality is probably exactly why Sora is so eagerly willing to kill himself to save his friends.
And that ain't healthy ya'll.
I kinda get the feeling too. In KH2 when he thought about dancing with her, she was still the KH1 Kairi (but of course he did not know how she really looked like in that moment) but when he saw her again he was maybe a bit shocked to see her change that way? People like to point out that he believed that she was safe on the island and did not know Rikus fate thus the different reactions, but wasnt she kidnapped too? So maybe after that point his own feelings changed? I mean he likes to help and protect people, so its not surprising that he still wants to protect her and she still could be his Light without it being romantic. Its just a bit telling for me, that Sora never had problems with thinking about her and the rest teasing him about this, but in KH3 he never once did that. Not even when he was with lovers.
I also agree that Riku and Sora scene often feels a bit romantic, but quite a bit of people say that this is only deep friendship and brotherly love. Thus my point in changing ones gender to see if that would still hold up. I just find it funny that its of course just friendship between them but every single meaningful action between Sora and Kairi is nothing but romantic. I believe in the end, that this game can support both ships. Both of them have hints in the games that can be seen as romantic but at least for me Sora and Riku feel much more natural as friends but also as possible lovers. We just had the chance to get to know these characters and their bond. While we are only told most of the time about Kairi.
About nobodoy dieing: Well people can die but yes death is happening not that often in this game. For me it would have been better if Kairi had just stayed death. Maybe instead of being killed of like she was in the game, she could have gone out protecting everyone thus being to exhausted to fight back. It would be a wonderful way to give Sora himself some character development and he still could have disappeared at the end because imo it was hopefully not Kairi that killed him again, but changing reality like that may have already meant that he was on deaths door anyway thus he just took his remaining time to save her. (I mean him rewriting their fate did not only save his friend and him but probably also millions of people that would have vanished after Xehanort destroyed the universe) So Sora accepting that you cant save everyone would have been a nice change.
But I can of course not blame him for trying to save her, because most Disney worlds did show him that you can save those you love through special powers and in this game only Hiro accepted his brothers and Baymaxes death. (Will and Elisabeth might not see each other much but that is probably still better than Will being death)