Generally it’s pretty much plug and play these days. Resolution/FOV/useful tweaks are all handled by DirectVR.
The one major tip that truly enhances the experience is using OpenTrack for emulating TrackIR head tracking instead of vorpX’s mouse based tracking. Arma III supports decoupled aim/walk with TrackIR, so you get look/aim that works pretty much like a native VR FPS. Unfortunately Arma III is the only FPS that supports TrackIR in this manner as far as I’m aware.