This is just what I've been considering writing, but far more advanced than I would have ever considered going with it. Absolutely wonderful! Please consider adding a "Desktop Wallpaper" controller that uses the same fade and randomization techniques that you use with the screensaver. All the code is there (set wallpaper from last image shown), You would just need to add an option and tweak the GUI a bit.
But Idea Informer isn't working. This is BryanMohr