After tinkering with many settings, this is where I am satisfied enough to play. I am maintaining 45 fps in the Huey Free Flight mission that I was using to test with.
Deferred Shading was too much of a hit for me.
I have in game Pixel Density set to 1.3 which reduces jaggy edges enough for me with no MSAA.
Oculus Rift
Windows 10
i5 4690K @ 4.2 Ghz
GTX 980
16 GB RAM
DCS installed on SSD
Nvidia driver 390.77