Awesome set-up.
As for wheels color, I think black is perfect for grey cars. Gunmetal seems a bit too matchy-matchy with Space Grey. Yeah I know coming from a guy with a black on black set-up
but I personally think that iswine color it can go hand in hand and go stealth. A brushed aluminum/brushed silver might look good with Space Grey though. I think your first set up looks good with the matte black wheels, just needs a little drop?
Definitely keep us posted with your decision, please.