"My previous research ( https://phish.net/blog/1539388704/setlists-and-show-ratings.html ) demonstrated that show ratings (with equal rater weights) are significantly correlated with setlist elements such as the amount of jamming in a show, the number and type of segues, the relative rarity of the setlist, narrative songs, and other factors."

If we believe to know the majority of setlist elements that typically correlate to a rating, would it make sense to list those elements for a user to individually rate when they go to rate a show? Subsequently a formula could crunch those numbers together to generate an "overall rating". Personally, I think I would stop and think twice about each category and probably be less impulsive with my rating after attending a show. Yes, it could drive some people away from rating due to the "survey-ness" of the approach, but at least you're able to understand and measure the impact of a rating based on those elements.