Quote - I often find myself wishing there were additional raytrace settings on the lights so that for instance they did only specular and didn't add more actual light to the scene

Easy: Set up a light, then go to the material room and change the light's diffuse color to black. You get a light that only does specular; Very convenient, I use them all the time. Only drawback is they still show as normal lights in the preview, so you have to turn them off while fine-tuning your lighting.