To put it in few words, this manga should never have been made.
ryuuki_fenikkasu
I read the first book or two of the manga as scanlations awhile ago...have to say, I wasn't very impressed, though it did managed to give a little more depth to Riku, and it was cool to see some of the Final Fantasy characters in a manga.
*snorts*
That was because the manga is based on Kingdom Hearts: Final Mix, a remixed and improved game released only in Japan in retailation for the US/Europe versions four extra bosses. It wasn't a whole different game though, here's a basic list of the changes (I am the KH Guru)
1: About ten extra Riku cutscenes, which is the 'more depth of Riku' you saw in the manga
2: A Cloud VS Sephiroth cutscene
3: Three more Ansem's Reports
4: Three Extra bosses
5: Four or Five extra monsters, including a huge mushroom in Deep Jungle
6: Two new keyblades, The Diamond Dust and the One Winged Angel.
khinsider.com has a more detailed list and screencaps and downloads and such.
Back to the manga, I read scanslations of it, and personally I think it reeked. Mostly because I found the drawing style supremely unattractive, and because the Japanese versions of the disney characters are just.... Odd. (This is a problem in the Japanese games too, but it's a cultural thing, not a story thing. That's another of my biases, I'll be frank.)
Also, it condensed the storyline, and when you get right down to it, the Kingdom Hearts story was designed for a
game, and doesn't lend itself to manga form. When authored, it was meant to be a story with lots of thrilling action between cutscenes, and that type of writing doesn't lend itself to reading. (Like when readinga Shakespear play VS seeing one. Reading: Yawn/WTF Seeing: OOH! BLOOD! SEX! GORE!)
You see my point?