I think I found it elsewhere, here are the comments from the screenwriter: Says Schumacher: “The Dorian Harewood character [Levi] was arrested, and he was in jail, and he found God, and he became a Jesse Jackson-like figure, and then, of course, the Phillip Michael Thomas character [Stix] was my version of Berry Gordy. It wasn’t based on Berry, but it was influenced by that. And Sparkle certainly wasn’t based on Diana Ross, because Sparkle is an innocent, whereas Diana has always been very driven, and ambitious—and I mean that in the best possible sense—whereas Sparkle is a child, she’s a pure soul in a world of turmoil around her, and remains true to herself. And Delores, the third sister, who gets very smart; she became political, and she goes down south and becomes an Angela Davis type figure.” See here for the whole article: http://spbvip.wordpress.com/2009/01/22/wayback-wednesdays-on-a-thursday-sparkle/
Wow his I like his original script idea alot. He seems to be very in tune with black culture at the time. His original script except for Sista dying is very positive and interesting. I think it could have made the movie(which is good) even better.