What the RENT movie needs most of all is a writer. Jonathan Larson never really finished it, wondeful as it is as a whole, and the 2nd act, despite the good tunes, is a bit of a structural mess. The story is tight in act one, since it's all one night. But then it runs out of gas. Getting that into story form -- finding beat-by-beat reality in that wash of death and redemption -- will require a damned good screenplay. The movie of HAIR was in development for years, and ended up almost working, but only almost. I think RENT has some of the HAIR problems. You buy the diffused focus on stage, but in a movie, it could lack momentum. Also, Mimi's final "twist" could look ludicrous and make Puccini look like realism in comparison.
Wouldn't Baz L been interesting??
"I'm a comedian, but in my spare time, things bother me." Garry Shandling