Thanks for the links, I skimmed the articles, they are very interesting and I will certainly read them later. They are not what I'm looking for, however.
What I'm looking for are empiric, preferably cross-cultural, studies on color harmony. I'm interested in work similar to what has been done for Unique Hues and Focal Colors but for combinations of two or more colors and for the notion whether people find these combinations pleasing, neutral or displeasing. I wouldn't be surprised too much if we couldn't find universal pleasing combinations but I'm surprised that apparently no one has done these type of studies.
May not be exactly what you want but you could look into the World Color Survey:
There are some interesting in-depth articles about how people build those palettes and ramps that you might find interesting:
https://uxplanet.org/designing-systematic-colors-b5d2605b15c
https://design.lyft.com/re-approaching-color-9e604ba22c88