I've never seen the musical, but I'm reading the book and my goodness, the AU retelling potential is almost as obvious as all the Fluttercord Beauty and the Beast stories. Granted, I haven't read far enough to see how it ends, but I could definitely see Rara and Applejack being Christine/Raoul and a slightly lovestruck/slightly more creepy Svengallop being the Phantom.

I would write this, but it would take 100k+ words to do it justice and I have too many series going on...