After some time without rendering anything in Rhino (maybe about 8 months?), I took a look at it again.
First of all, the Rendered mode looks so much better for me than what I was used to. I don’t know if it is because I was using V-Ray in the past and the materials were not previewing correctly (v-ray doesn’t care about some useful Rhino features, so that would be no surprise) or there was some development done?
Anyway, previewing scene in Rendered mode is much more eye-pleasing now, thank you for all the work!
To not make it all sweet, I need to mention about huge viewport performance drop if there is an Ambient Occlusion texture turned on in the material.