I’m not sure we will get the Enscape material editor for Rhino too. I ask for but got no answer. So, I suppose so we need to live with the Rhino materials. I think, it could be good if we try to get the last little enhancements for Rhino 6 now. Please read and post here.
https://discourse.mcneel.com/t/enhanced-material-ui-and-options/51977/2