I was under the impression that the only thing "Blur" does, is to blur the part of the view that is covered by the darkening rectangle behind UI panels, in order to make the text stand out even better against the background..?
As for Ambient occlusion: Not only does Elite's implementation gobble up more GPU cycles than it is worth in general, IHMO; But it renders outright eye-strainingly wrong for almost all VR headsets.
The per-eye field of view for all but a few HMDs, extends farther out to the right than it does to the left, for the right eye; And vice versa for the left one; And it appears post-effect AO shaders are usually written with an assumption that the centre of the frame is "straight ahead", which is not true when you have asymmetric camera frusta (matched to the HMD per-eye FOVs), resulting in the AO rendering differently for the two eyes, producing a dark shadow in a given corner for one eye, but not the other.
This problem gets worse the greater the asymmetry, which is to say the more FOV, and the less stereo overlap you have; Terrible with wide FOV headsets, like Pimax; Quite acceptable with the original HTC Vive, which outshines most when it comes to stereo overlap, and lets each eye see almost as far out to both sides.
