I put my GTX-1070 threaded optimization on "Auto" and got an immediate 10 to 12 fps improvement. So with settings nearly maxed out, i'm getting 28 to 38 fps. This is flying over the desert though too. Chino to Las Vegas. A denser scenery will for sure chop it down.
System i7 3.4ghz, 16gb ram, GTX 1070