As a MMJB convert I still use the MMJB custom "Preference" tag to rate tracks, this could easily be converted to the star system, but I find actual words to be more easily understandable.
MMJB had standardized on the Preference possibilities of: Excellent, Good, Fair, Poor to which I added Fantastic (since MC9 lets me use any text and I no longer need MMJB compatibility). Plus, I also still use the MMJB tags: Mood, Tempo and Situation for further categorization.
After ripping a number of cd's in a session, I make a first pass to categorize using the above ... the Poor's are pretty much deleted rather quickly, otherwise this is basically my criteria:
Fantastic - a track I can listen to over and over again without getting tired of it, and that I want to make sure to let my friends hear ... typically always have one or more Fantastic compilation cd's with me in car, hotel, etc.
Excellent - a track that is always listenable in any situation
Good - a track that may have some obnoxious sound/instrument/mixing or may be overly repetitive or is just not quite Excellent
Fair - a track that is difficult to listen to, but not so bad as to be Poor and trashed
I keep the Goods around because there may be times that I'm sort of tired of listening to only the Excellent and Fantastic tracks. I keep the Fairs around because I haven't yet decided to trash them or maybe I think there are other friends (or yes even myself) that might like to hear them at some future time.
I recently went on a trip to the coast. Being an older married guy who was looking forward to some nice r&r we chose an upscale hotel with balcony overlooking the water. I brought along a Sony mp3 boombox and 2 sets of Sony 7506 headphones (btw these are superb and to me sound better than any of the other 750x's and even the Sennheiser HD600 which has some missing mid-highs where the cymbals reside).
Before the trip, I easily made compilations for the various moods I thought we might be in:
Morning:
Preference=Fantastic, Excellent, Mood=Upbeat, Tempo=Fast
Afternoon:
Preference=Fantastic, Excellent, Mood=Mellow, Tempo=Fast
Night:
Preference=Fantastic, Excellent, Mood=Mellow, Tempo=Slow, Tranquil
I also made some compilations using other combinations but the above turned out superb!
I also use the Situation tag with my own made up values like: Dance, Dream, Romantic