I'm not good at the game so take my ratings with a massive grain of salt. I mostly go by how I felt after playing the map, and I think song choice is an important factor.

good song = songs I probably listen to on my own because they are good and I like them. Please map more of them!!
awful song = songs I would rather put my pee-pee in a pencil sharpener then have to listen to again. Please don't map them!!