I can't really add more than I have as I'm already knee deep in a personal project. I will note that the 2 identical texture maps into the blender running into hsv into scatter is nonsensical, at least to my eyes. Blenders are more resource heavy than a 1x1 multiply, in particular if they're not actually doing anything. So there's that. I would get rid of the additional image map and the blender, run the image map into the scatter color (and the preview diffuse at 0) and the scatter into the hsv to the alt diffuse... which seems to be a typical set up.

And get rid of the reflect_light_multiply (again). 

Have you tried the point light trick I mentioned earlier?

I take my leave.