Super dirty lighting update. There are a few things wrong with this shot - too dark in the back and the sun is a little weak and pale and the ambient is a bit weak as well. Those issues have been fixed now just don't have a proper shot of it. Also started doing some selective diffuse boosts on colored surfaces. Will probably do on one or two bright floors too.
Also temporarily pretty much all diffuses are single colors now, so they will start popping in with some more stuff soon. But it will be a gradual addition and we will try to focus some more on material definition and trying to vary that up a bit more. The test here has more broad variation than before making the whole object bright or dark/colorful rather than having a lot of variation within each piece. But do remember it's just colors now so this is the extreme case in the other direction really 
[Blocked Image: http://philipk.net/other/hpk_scene_WIP08.jpg]
I did a pass on all textures, brought them up to a 186 ~ 200 mean, chromes are around 140 ~ 150 mean, i would go bellow that but without a cubemap it starts to soak the lighting with how black it is so you have to make compromises. I'm also currently doing a pass on all specs and gloss maps, added a lot of contrasty and detail to the gloss, and a bit more noise to the spec. I also added the AO to the spec and remove the AO from the difuse, in fact i removed most noise and detail from the difuse maps, i want the slight noise to come from the gloss. (Good example is that floor tile on the bottom left with chrome, rubber and plastic material.) feel free to tear me a new one