I have a similar situation in a rental unit - a big wall of glass on one side, a brick wall on the other, and wood on the other side. A brown rug on the floor. Very dark, and worse because the patio out back is enclosed with 8' high walls and half-covered by a second story overhang.
I put in extra lights (not hard-wired but rigged to turn on with two switches), and I brought in white area rugs. You could do the same - but since you own the place you could wire the lights. And about the rugs - yes, they do get dirty, buy cheap ones from Home Depot or Ikea (if you have an Ikea near you) - then just replace them every year or 2. Less of a pain than trying to clean a nicer rug (and cheaper too I think).
You could try stripping the wood and varnishing it to see if you can lighten it up. Just experiment on a small corner of the room (behind a piece of furniture) first.
Anyway, good luck with your dark home. I'm living well with mine!
