According to Farcebook;
The compositor service moves distortion rendering from the application process to the OVRServer process using texture sets that are shared between the two processes. A texture set is basically a swap chain, with buffers rotated to allow game rendering to proceed while the current frame is distorted and displayed.
Layer support allows multiple independent application render targets to be independently sent to the HMD. For example, you might render a heads-up display, background, and game space each in their own separate render target. Each render target is a layer, and the layers are combined by the compositor (rather than the application) right before distortion and display. Each layer may have a different size, resolution, and update rate.
The API simplification is a move towards the final API, which primarily removes support for application-based distortion rendering.
From my lesser knowledge of programming, but greater cynicism as a sys admin. I'm guessing you need an insane video card cus that's whats doing the grunt work.
There will be a reason for these insane specs that's not just Candy Crush related.
I suspect that LFS being popular and low spec upset 'some pile of money' so the specs were changed so 'some pile of money' could make more cash.
Check out the alternatives that aren't owned by a bunch of 'redacted'. A collection of 'redacted' pointless 'redacted' moneyhungry 'redacted', 'redacted', 'redacted', and 'redacted', 'redacted', up their 'redacted', 'redacted', 'redacted', corporations.
There are other systems that use opensource api's that, in my opinion, are better to support.
"But HTC has a huge advantage over other VR headsets in its partnership with Valve - there's a massive amount of Steam games that already have the necessary code to work with the Oculus Rift, and Valve is releasing an open source API (application programming interface) so that developers can make their products (not just games) compatible with SteamVR." http://www.wareable.com/vr/htc-vive-vr-headset-release-date-price-specs-7929
Yes, Occ Rift looked awesome and was the first. Then Farcebook came and .......
Look at all the options rather than just one. The 3D concept is coming, just support the ones that fit with LFS. The min specs for Occ Rift are so far away from your stated vision for LFS it's not funny.