Sounds like you need to head to the Great Basin. Lots of boondocking opportunities. While there can be afternoon thunderstorms, by the evening the sky has generally cleared up nicely. In many places, one is miles from any town or even a ranch, so it is DARK out there. There are dirt and 4x4 roads that go up pretty high on some of the mountain ranges. Have to be a little careful about them at night so as not to do damage or puncture a tire. I've been to the top of Prospect Peak out of Eureka, driven most of the length of the Diamond Range right along the ridge line, and been to the top of Roberts Creek Mountain back before the closed all the roads up there. Amazing views, clear air, and little light pollution.
For something a little more developed, you could easily get your rig to Wheeler Peak CG at Great Basin NP. You'll be pretty high in elevation and it's a gorgeous CG and area to boot. Other options include the NFS CG's up Lamoille Canyon and Angel Lake in the Ruby/East Humboldt Range.
But for just boondocking, there are so many out of the way places in Nevada that meet your criteria, you could spend years checking them all out. Maybe check out the Toiyabe and Toquima Ranges. Have camped at some of the NFS CG's there (most are free) and had the CG's to ourselves.
