My current vehicle is black/black (Infiniti M35x). Looks great and the seats are heated/cooled so the comfort factor is OK. It does take a while for the seats to cool down on a hot day and in a suit it gets uncomfortable but bearable.
My problem with black is that it attracts dust so much....we also have cottonwood trees here in the Mountain West which create a fluff and "dander" that requires consistent cleaning.
I think it looks really tight to have black/black but for me, i'm going back to lighter interior...as a matter of fact, buying the exact car color scheme you describe....oyster/black interior with the anthracite, graphite exterior. Also tired of cleaning the black exterior although it's still my favorite color when clean on almost any car.
If you go dark, spend that 2100 on the cooled seats would be my suggestion, or just bear it for 3 months/year (dependng upon where you live)
As for the HUD, I saw the same thing. My sales guy told me that it's a known issue with polarized glasses, you weren't crazy. I skipped it when ordering the car as most of my shades are polarized....