I have a GTX 780 - not the newest, but still a good GPU running Battlefield 1 quite good. I did my test looking at all 4 cores, and both threads of each (i7-4770K @3.5) - and none of them reached 30+% - but with what I read here that might actually make sense as the various tasks are always waiting for another task to finish. I did notice a bump up on GPU usage when enabling both Bloom and AO - but no change in CPU - though still I was below 30% GPU also.
So as it seem hardware can really only do 'so much' to repair performance I did some bechmark of the things that seem to cost the much (of things that can be toggled)
I ran two tests in different environments and found that compared to normal FPS I lose about 52% from having reflective floors, about 9% by enabling a gentle amount of Bloom, 12% by AO and 20% with Bloom and AO combined.
Just incase anyone is interested in some bechmarks of the "new" eyecandy

Btw - is there any way to toggle reflections on/off? I disabled them in my map-script for the floors to test.. I could not seem to find any cvars disabling map-enabled floor reflections.
