I wanted to build a lightweight “trail” bike, as an ex weight weenie xc type who’s started riding gnarlier stuff.
I’ve ended up with a Scott scale 720 frame, with rebas at 120mm, hope hoops with Stans arch rims. Zee rear mech, xt shifter xtr m985. 1×10. Heavy slx cassette. Xt brakes, 180/160. Renthal 740 alloy bars , and charge lockons
For more xc rides, I put on SPD’s, Thomson post, and maybe switch tyres to crossmarks. For more gnar, it has flats, a reverb, and a Hans dampf/ardent tyre combo. It’s about 22.5lb in light mode, 23 in “heavy”.
Biggest compromise is the fork. It’s just a bit rubbish. More weight won’t fix that though – more money will!