Been to most of those places. Check to see what is open now with all the craziness. You taking any toys beyond boards? I've never been able to go for more than two weeks. But in a couple of years I'll have all the time in the world!
Thinking about this more. We were fortunate enough to be able to get away for some one and two week treks with our boys when they were younger than your girls. Rushmore, Yellowstone, Rocky Mountains, Crater Lake. All sorts of places in the western states. They're all in their 30's now and we still talk about those trips. They definitely make life long impressions. Two of my sons have RV's now and the third really wants one.
PASS IT ON!