I don't bring any of the spn offs into it cause they are cash ins and usually retcons.

Sephiroth does have a lot more depth than Rufus. people who use the word "deep" are usually the kind that are finding something in nothing and trying to appear intellectual....and failing.

We learn about Sephiroth's past, which is already more than we know about Rufus. Rufus is cool, but he is not expanded on, and he needn't be. He simply serves as the head of Shin-Ra