Hmmm. Issue #1 surfaces.
This isn't major -- however, this is a similar issue to one I once noticed with a D800 camera body I rented as well. Any thoughts on this would be appreciated.
I have four Nikkor lenses at my disposal, currently: 17-55 f/2.8G (DX), which I have no need to use on my D810; 24-70 f/2.8G; 50 f/1.4G; 70-200 2.8 VR (I, not II)
I noticed looking through the viewfinder that that the 24-70 looks somewhat dim. I took two test shots, one with my 50 and one with my 24-70.
Settings were exactly the same for each, same lighting conditions:
50 mm (obv), f 2.8, 1/60, ISO 320. I uploaded to CS6 in RAW, opened at default, exported at the same settings.
The 24-70 is indeed somewhat dimmer.
To avoid showing you all of my subsequent samples with various lens configurations and settings, I'll leave it at this:
I went through my four lenses, and found that, with the same settings, the 17-55 and 50 were brighter (and in fact, roughly the same brightness) than the 24-70 and 70-200 (which were roughly the same dimness). (I'm confident that I repeated this enough times to determine that this is actually the case, and not some fault of the testing.)
So basically, what's going on? Is this a body issue, or a lens issue? For certain though, even looking through my viewfinder with the 24-70 and 70-200, it's clear that they're dimmer than the ambient light, and it's translating to the images too.