Nemo was a depressive, idealistic revolutionary, who gave into despair. Reinhardt was a full-on psycho who sold his soul, based on a kind of death wish, and a belief that the black hole was some kind of gateway to immortality. Dark stuff for a Disney movie!
Also, our plucky heroes may have miraculously survived crossing an event horizon, but where the hell are they? Supplies are going to be an issue.
Before, they were searching for "habitable life" [sic]. Now, the same, but much more URGENTLY!
So we need, like, a "stargate sequence", but we've got to play to the evangelicals. Also, we can that Faust thing literal. "Maximillian" sounds a LITTLE like "Mephistopheles", right...?
Also, this movie finally gives us some interesting computer graphics effects on screen. They're wireframe and monochrome green!
Technically, "Alien" had some computer graphics before this, but they were kind of texty.