So I was re-watching the Strife video the other day, and I completely forgot about this request. But ever since I picked up Dungeons and Dragons and I wanted soundtracks to play in the background while I take the role of the Dungeon Master, I've been on a similar quest.
My method so far has been labelling what sort of emotion I want to convey, rather what I think the music is trying to convey. For example, I have started out with 'Medieval Tavern' for music I would expect to play in a tavern, while 'Mysterious' will be played while my party is in a dungeon and isn't in any danger. 'Sadness' is self-explanatory, as is 'Battle'. 'Epic' is for when you need a bigger sound for a particularly notable moment, such as boss fights or a setpiece. I need to work on the naming conventions and start branching it out into different genres, but if I make any notable progress, I'll update you all.
The other thing to note is I'm using Spotify for my playlists. This is less than ideal for Ross's purposes, but I'm hoping I can train the machine learning system that recommends songs to recognize the differences in moods. It's a long shot, but I'm going to try anyway.
I'm not sure if the change in perspective is helpful in any way, but I will keep chipping away at this conundrum and see if I can find a system that works.