Great questions. The melodies don’t have to be recognizable, although that is fun in a way, but original music is nice too. Sometimes I find it frustrating when an album doesn’t have enough allegro for jump combinations. The tempo basically has to be just right to work (very quick), otherwise you won’t be able to get off the floor!! And it has to make you want to jump. One album I have has a track thats the right tempo, but it makes me feel nervous and stressed.
A beautiful adagio with a sweeping melody is always inspiring. Waltzes are necessary as well, when I’m teaching beginners, they are often too fast for me to be able to teach them the step because they are just learning it. Sometimes I end up having to just count, or I sing Edelweiss
Also, because waltzes always have so much rubato that can really throw a beginner off as they’re trying to learn the step (although I admit its more interesting artistically).
It doesn’t have to be just piano, either. Scott Killian has some albums that are digitally orchestrated. Something different and unique would probably be welcomed and appreciated. Dancers need to be inspired by the music!
Let me know if I can answer any more questions or help in any other way. Nancy Malmed, the woman who owns the studio where I teach, has produced several albums, although she hasn’t put any out in many years. I think she was one of the first to produce ballet class music!