Oh I went through the Kingdom Hearts game script on Gamefaqs, and did a find-replace for every instance of the words 'heart', 'darkness', and 'light'.
Heart apears 263 times, darkness appears 68 times, and light appears 52 times. Strange I could've sworn that darkness appeared more than 68 times but oh well.
1) seems to focus more on original characters than disney characters
2) better disney worlds to visit
3) no stupid boss fights
4) no shitty jumping puzzles made shittier by a shitty camera
5) ability to skip cutscenes