There are similarities, but you seem to be looking in the wrong places. Oh, and people, TN worked on KH (who previously worked on FF) so . . . there's some religious references, considering that FF is built upon them . . .

The only one I think you hit on was the Light/Darkness thing . . . and here:

"A light shineth in darkness. And the darkness comprehendeth it not . . ."

But . . . that's a common theme, but a good one at that . . .