"Is there enough non sexual, exclusively gay content or gay perspective programming to last very long?"
I think there is. Gays are humans, and there are always new interest, hobbie, ideas, news, that goes with every group of human beings.
Take Chinese for example. There are asian channels, my mom watch it all the time. Are there going to be enough chinese content for the channel to continue with it's programing? Of couse there is.
But I do agree with you that quality is most important.