The only recommendation I can give you is to set up a custom 1080×1200 resolution in nvidia settings.
As strange as it may sound game looks better in this resolution + some anti-aliasing 2x,4x,8x) than in for example 1600×1200.
That is probably because 1080×1200 is the rift’s native resolution and things aren’t as blurry as they are in other resolutions. Additionally in 1080×1200 it runs considerably smoother than in other resolutions I have tested.
The only problem right now is for vorpx to save settings across restarts.