'Your face is...' as a comeback is witless and irritating. perhaps a pet-peeve, but I'm sure there are others who will agree
I use "your face" and "your mom" as comebacks all the time, but only when I know the resulting comeback will be highly inappropriate, so I can act like I suddenly realized it halfway through and backpedal badly to great comedic effect.
It's dumb, but it gets a laugh at work and tends to keep people in a decent mood. I find that your face and your mom suit my purposes perfe--OH GOD THAT SOUNDS WRONG. I DIDN'T MEAN IT, I SWEAR.