Same properties for all the materials and face adds

It’s a little bit confusing to have different blend modes for different things and also being not able to control alphas the same way for all the types of material. For example, I can use “add” as blend mode for some things, and for others I can’t. Also, e.g. I wanted to make a transition from 0 to 1 with the alpha of a matcap material, and it doesn’t have opacity control, while other materials do.