Just to get this out of the way this has nothing to do with romance or ships. I don't care about any of that stuff and it's not the point of this thread.
Basically I'm wondering what the community would think about an M or a T rated kingdom hearts game/novel. Obviously this will never actually happen, I'm asking the question because I'm wondering if people think the theme of the story would be enhanced as a result. I think one of the things holding back the series thematically is darkness isn't really "dark". "Nothingness" doesn't really feel like "nothingness". It's easy for a game to highlight the goodness of "light" because we have the real world to compare it to, but darkness in the game is sort of underwhelming isnt it? And the savagery of darkness (and light) isn't given much room to be explored. As far as the light goes there is only the keyblade war and the scene where Eraqus tries to put down ven.
Because of the way the series is formatted, the few savage moments there are feel out of place. What would otherwise be a bloody massacre instead amounts to just a large scale keyblade battle. Strelitzias death, very sad, but its the only real death in the whole series that I can think of and it happens in a phone game. you also have Xion, but she really just evaporates to rejoin Sora, and then she comes back in KH3. There is no real savagery or weight behind these losses so the atmosphere of the worlds never really change.
On the other hand, you have this secret movie (at the end of kh2 i think?) that really highlights the desperation of terra, aqua, and ven and the savagery of xehanort.
Xehanort drops vens frozen body off a cliff. In KH3 the most savage thing to happen is he strikes kairi once and she evaporates. There has also been a huge issue in my opinion really showing 'worlds falling to darkness' and what that really means. It seems to happen so frequently now that I find myself just not caring, and maybe it should be feeling inevitable but there should still be some weight behind losing places that we've revisited many times. KH3 did have some good moments, but they were also undermined within a couple hours of each other. The desperation I felt in the first few games has been replaced with the sort of desperation I feel watching Goku fight anyone in Dragon Ball Z, knowing that all the characters can be revived using the dragon balls.
I've always felt like Kingdom Hearts is at it's best when the character's are struggling the most. Stuff like aquas experience in 2.8, xion fighting roxas, the above graveyard battle, etc really contrasts with all the lighthearted disney worlds really well. Unfortunately the way that a lot of these plot points get resolved has been through the power of friendship, or something like it - and it really undermines the character's struggle. Aqua being returned to normal by Sora after years in the realm of darkness is a perfect example of this. As far as we know right now her long inner struggle didn't even lead her to have any sort of revelation about the darkness. Among the masters now, Riku alone is the only one who seems willing to use darkness which is sort of strange given all of their experiences.
There is plenty to say about the general writing and implementation of the Disney worlds, but all of that has been discussed a thousand times. I'm also not suggesting that the disney worlds should be thrown away, I think they have their place in the story, I just think that the parts of the story that strictly deal with things unique to the Kingdom Hearts lore would be enhanced if it wasn't held back by the E rating.