I actually don't have a whole lot of favorite skating music. I mean, I tend to really like Raul di Blasio and Camille St. Saens, but as long as it is pretty and the skater is interpreting it well, I'm not that picky.
Of course, my least favorites are just ones that are heavily used in skating such as Carmen, Firebird, etc. There's also some pieces that I feel should just be left alone (unless you're capable of making it a masterpiece), because a skater has made it their own (instances such as Michelle Kwan and the music Tosca... whenever I watch another skater use it, I end up picturing Michelle and wish I was watching her instead.).
One thing I'd really like to see is a skater using music from Star Wars effectively; some of the music is just so powerful and some is really beautiful. I know that plenty of skaters have used it, but I don't really remember the programs very well and I'd love to see one that really stands out (in a good way!).