I thought the movie was the godsend Anti-Uwe Boll I've been wanting all along.
Since it's a story continuation, I think it can get away without a lot of character development... As we all already know what happened and why they are the way they are. As for the baddies, they were just like Sephy... Mommy obsessed, what's to know.
I thought the idea of Jenova's cells infecting people through the lifestream, Sephiroth's intentions made clear at the end, Cloud's anti-social behavior, Rufus's manipulations, everything involving Reno, and the general state of the world were quite brilliant pieces of plot actually.
The movie is worth 20$ just to hear Barret say "Thaz some crazy water GAHAHA" at the end.