It is interesting to note that it is that same community which is so loathe to enter the Material Room and for whom Parmatic was designed in the first place. (or so my fevered imagination would have me believe)
I would like to include this functionality into a character I'm developing together with someone who's quite successful at creating characters, Bill. The dials work quite nicely for the most part: I can dial in tint strength for lips and eyeshadow as well as shininess for the same. Just reading a thread (on RDNA) on how I might be able to parameterize colours for the same regions (R,G and B values separately)... so it's just the saved parameter thingie that isn't behaving as expected.

Oh, and thank you, Bill, for pondering this question for me...

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

Metaphor of Chooks