I've gotten some nice shaders that weren't that complex at all.  Initially, they were essentially the same materials as my P4 materials.  Everything from the P4 room is in there, and getting them to look as they did in P4 wasn't too much work.  I just try to link everything direct and avoid the math nodes.  I'll often use copies of the same texture at different strengths to give a little more control (since it's already being referenced) over each channel. The material room is one of my favourite parts of the program.  I can't believe how long it took me to try UV scaling!