Green > brown all day long.
I don't understand people that would rather have 325 days of sunshine but live in a barren desert, over 200 days of sunshine with lush, verdant scenery. But people are different.
Far Eastern WA can be pretty nice (next time you're in Spokane try Manito Park). Lots more trees, hills, etc. NE Washington as well. The West part of Eastern WA, like Chelan and Okanogan County are great too. In between? Not so nice, lots of flat land and blowing dust like you say.