Runaways was a musical in 1978 that pushed the limits. Although it only had a short Broadway run, it had started downtown at New York Shakespeare Festival. It pushed the limits because it was a musical about kids that ran away from their homes and what they encountered in the real world. It was more social commentary than Broadway musical. While it doesn't fit all of your criteria, it certainly didn't make the huge mark that the others on your list have made, it could be considered a footnote on your timeline.
If anyone ever tells you that you put too much Parmesan cheese on your pasta, stop talking to them. You don't need that kind of negativity in your life.