Well this one didn't come out as hoped, but I figured I would stick it out. The cracks on the ridges are WAY too overpowering and regular, as I forgot to break it up a bit. And I should go back and fix it.
But after a "combined" rendertime time of 232 hours and 23 mins (for 800x600 @ quality 0.8 ), I think I'll live with this image as-is, for now.
I rendered this on 4 cores (so it effectively only cost me 96hr, 26mn). I am very confident the culprit was the population of pines in the valley. I used a large pine tree model with some custom complex tweaks in the object shaders for added realism. Additionally, I noticed the populations behind the mountains were also rendered (no way around it on this image), adding to the time significantly. Hopefully they'll have this fixed in the future.
Rendertimes for each core:
core 1: 96hr, 26mn
core 2: 64hr, 1mn
core 3: 37hr, 46mn
core 4: 36hr, 10mn
I am satisfied with the lighting and how the snow sticks to the surfaces. The foreground pine has custom tweaks to simulate frost and snow on the needles, and this seems to have worked quite well. Additionally, there are background stars, though hard to see at this resolution.
Definitely more work to do.
This image uses alot of my older groups setups, which I've since updated.
Attached is a screen of the nodes for anyone who is interested.