I switched CAS to native and kept sampling to 1.0 after Update 5 flickered like crazy at all times. I'm getting a reliable 60FPS (fixed) in space, and 45 FPS on planets. I have a GTX1060 and display is on either 1920x1080 or 2560x1080. I even gave it a try with surround Physx across all 4 monitors and it was fine.
I think the variance is probably more what else the PC is up to, and the base PC spec. I have a Samsung Pro Nvme, which elite is installed on, and an 8 core piledriver processor. (Toasty warm). Ages ago, I went through all the windows services that were running resident on the card and disabled a bunch of the unwanted stuff in services.