As a start, set the diffuse & ambient colours of the reflecting surface to 0 (black). Anything in these will be included in the reflection, and will tend to "wash it out". The "Background" in the reflect node is exactly that - it's intended for a picture that shows "what's in the background". I haven't worked out the best way to use this yet. My current (simple) method is to add anything I want in the (scene's) background into the scene, set the "reflect" background to black (I think, I'm going on a wonky memory here - it was either total black or total white..) There's scope here for improvement, but I haven't worked it out yet..:-))