I think your spec list choice is pretty good, very similar to mine.
The "single front fog light" is actually the radar unit for the adaptive cruise control and lane assist etc. I didn't spec this and haven't really wanted it but I now think it would have been nice to try. I'm gonna put it on the RS6 PE spec.
I have black panther crystal which is stunning, essentially black but flips between purple and green, a lovely surprise when the sun comes out. If its a black B8.5 you want then worth taking a look at this colour in the sunlight.
Electric tailgate is 2014 or later, not earlier as it became standard spec after that, these is a thread here somewhere with all the details on and which year they were added.
I wish I had gone for carbon dash inserts and not the pion black but I wanted the quad black (paint, optics, leather and dash) but its show the dust so quickly, carbon would have been better.
Sports pack is great, 20" wheels, Sports Diff, Sports exhaust etc. I wanted rotors until I saw the V-spokes and loved them, now looking for 20" Rotors for next years winter wheels.
Pan roof is nice to have, B&O better than standard and its a common upgrade as its part of the Tech pack so you should find many with these. Tech pack is good, gives you 3g+ MMI with google maps and full bluetooth audio etc, stunning slick and works well. Google earth gives you street view and terrain maps and Audi connect gives you full integration with you desktop PC for navigation locations direct from google maps ( I never tap in a location while sitting in the car).
Black optics eliminated that Aluminium trim you don't like. The extended leather on the armrests is a nice thing too.