a few quick observations...
your Thomson Elite seatpost while very strong is not the lightest...
I'd consider USE Alien Carbon post..
the Sachs chain can be bettered with a KMC-X10 (10 speed chain, but works just fine on 9 speed and off-road).
XTR QR are not light (120g a pair).
Consider Heylight Ti QR at around 55g a pair
Specialized Nimbus EX tires are 600g a piece. I know they have "helpful" "flack jacket" protection.
Why not try Nokian NBX lites? THey are a 480g 2.0 tyre. As opposed to your Nimbus ES 1.5's at 600g.