This last weekend (fri night) I decided on a whim to head out to West TX (i'm in Abilene). Solo trip.
Departed for Monahans shortly after dark, got there late, but had clear skies and a BRIGHT moon.
Didn't take as many shots of the dunes as I'd like, but I'll go back soon enough.
All the below shots were with 6D and Tokina 17/3.5 AT-X AF
#1 and 2 are my favorites here, you really got a sweet looking shot in #2. I like what you went for in #4 with trying to get the sun into the shot, but there are lens flares all over the shot, down in the sand, etc.. that really take away from that one. When trying to get the sun into a shot like that, it's best to take two shots, one as you did, and then take a second shot where you cover the sun with your finger. That will prevent all the lens flares going all over in the shot. Then just blend the two exposures, using a layer mask to leave all the lens flares out.