Reasonable reasoning. I finally ended up on a raw sienna highlighted with a desert sand color for all of my terrain - I figured out later that the amount of orange I was seeing in the visuals was actually an error on the TV's part, but I really liked it, so left it. It works well, and I can gray it out without it seeming dulled, which is a real trick sometimes.
If you decide to move away from it, I would highly suggest just using the dark as a base, and using gray and light brown mixed with it to highlight up. It ties the old terrain in without making it seem out of place. I am doing that with my VSF and Fallout stuff, so that I can use both on the terrain boards I have made.
All in all, great stuff!