(an early version of my MOC had the same mask too)
Pretty cool stuff you have here! Some of the things like the gap on the knees and the silver fingers bug me, and I recommend you making the arms have open ball joints instead of locked so you have more realistic articulation.
The torso is also a bit blocky, but some other things like the way those parts are attached to the socket on the upper legs is pretty clever, the gears mimicking a gearbox is also a nice touch too.