What do you have against turning the rotors?? Its cheap. The rotor have a glaze that builds up on them. I always turn or replace them. If you don't want to hassle with getting them turned, at least hit them with some sandpaper and cut the glaze off of them. Try to give them a "non-directional" finish by moving the sandpaper in a circular motion as you make your way around the rotor. Maybe 400 grit paper?
Or you could use EBC pads. They come with a built in coating on the pads that cuts the glaze off the rotors.
Don't short cut a brake job. Its not worth it!!