@Headwarp,
Thanks for some good insight into your experience and for providing some recommendations.
I use a TrackIR 5 and I would be thrilled if I could get a steady 45 FPS. Unfortunately, as I mentioned in my previous posts, I seem to be stuck in low 20s ad vitam aeternam.
I also get up to 60 FPS when I'm basically looking at... nothing.
I'll keep my trials and errors testing going, and hope that Vulkan may help us all someday. :)