the shading of the 3d elements is going to be the least of anyones concern. the way i see it, teaching 3d across software is a very hard thing to do, and the colors arent going to do anything more then to confuse. the colors will all change when materials are added anyways.
what you are doing is changing the color of the lights, which is a bad idea. this will distort the viewport preview colors, making materials unpredictable and confusing. i cant stand the colored defaults that blender starts with.