Recently i decided using 2.80 for my project created in 2.79 and experienced some issues with materials. Imported materials from 2.79 seem to work differently on 2.80 to those created in a clean 2.80 blend file. My main issue is that i cant toggle nodes off on any materials of imported blend files to get those kinda "simple-mode" materials. Creating new materials behaves the same.
Also i dont understand the differences of "Viewport display" and "Surface". They both have colors which could be set. i just want flat colors as materials with metalic shading or transparency nothing too special. i also dont use any textures.
clean 2.80 material:
imported 2.80 material: