Well color blending is whole another can of worms; there are no easy answers there. Mixing RGB values even in linear space does not yield always "correct" results. More problematic, I'm not sure if there is even well-defined correct result for generalized color mixing/blending.
Even something as simple as a proper gradient between two colors is surprisingly difficult. I think I finally cracked that one though: https://stackoverflow.com/a/49321304/5987
Color mixing is easy if you're mixing light, just add together the linear intensities. Color mixing of pigments is a different order of complexity, because you have to consider that pigments are both transmissive and reflective and there are other effects like dot gain and spectral lines to consider.
https://www.youtube.com/watch?v=LKnqECcg6Gw (Computer Color is Broken, MinutePhysics)