I knew a guy at college who modelled robots in a similar way.
With regards to your robot, couple of things stand out in my mind:
Toes seem rather long
Thumb isn’t long enough to be of any use
The ‘briefs’ / ‘undies’ / y-fronts in the top image seem very small.I think with some minor tweaking of proportions, you could have the makings of a nice little bot here.
Looks very nice; can’t wait to see it with the joints included. At the moment he seems to be a bit slumped forwards in a Marvin the Paranoid Android style. Is this going to be his basic pose?