I want to give this a bit more thought but I have 2 quick observations. First, regarding the music analogies I tend to think of the architect as being closer to a jazz musician than a rock musician or a classical musician. The jazz musician can write his own music or he can take the chord structure of a standard and improvise to make it his own. Similarly, an architect can take themes that have been used by others and, depending on the property and his/her particular tastes and talents, improvise and make something that is uniquely theirs. This ability to take something familiar and make it your own is a special talent both in jazz and in GCA. It is distinct from playing a "cover".
Second, the great period for serious criticism was in the Golden Age when there were fewer "rules" and the architects were trying to figure out what made a course great. Less history, fewer preconceptions, and a smaller industry made for greater freedom in analysis. When the turn to "minimalism" came, it was a rejection of several decades of thought and an attempt to return to some of the Golden Age verities. The problem is, just as in the Golden Age, there remains significant disagreement as to the validity/identity of the "verities". I really don't think the ratings try to address this issue notwithstanding their criteria.