Q: whats a good trick to finding music that has similar emotional/harmonic content to something particular you like, when most searches by association seem to be genre or artist based?
A: impossible. you'll only see/hear it in context. try watching movies or videos. the movie may cause you to develop more of an attachmental bias to the music, but that's actually the way it's supposed to be. the music you liked before almost certainly came to you packaged in some way contextually. it's no accident that most people's favorite songs is something they heard in a movie, in a game, or while something was happening or while they were somewhere. you always are somewhere, that's just the law