I find if you take higher numbers down to about 10 percent, and then change the environment map your tilesets point to, you can make a huge impact.
One of the things I prefer is a much less shiny metal. Detail your metal graphics so they shininess is already half done, and then change your local environment maps to fit the scene. The only problem I found with that is that the environment maps on tilesets carry over on your person if you move to another area with a different tileset. I put quite a bit of time making envmaps for lava caverns, rural, forest, and a generic torch-lit dark place, which I then used for caves, mines, interior dungeons, and crypts.
I also played with some shiny core environment maps which were built for general use. But again, those only look really good if you redo the metal textures the map is applied to. It becomes a job. I did find a few which worked excellent for futuristic super smooth armor.
My major problem with the whole environment map is that it is camera based. Not useful to me at all really.
