Hamilton is a big one waiting to happen. You could do a great Street Commercial CC to My Shot, or a waltz to Helpless (I think it's 3/4?). I think South Pacific, Oklahoma and Carousel have been underused.
What annoys me most is the producers' tendency to blur the lines between musicals and movies weeks, so they put stage musicals which have had an unconvincing film version into movie week and Disney movies which have an unconvincing stage version into Musicals Week.