I had a quick doddle over your piece - quite a bit of cut & paste really.
So frame by frame
1/ Yours
2/ Made a basic anatomy fix for the length of the body.
3/ Repositioned eyes to be more human like
4/ Gave the shoulder pads a bit more depth and purpose
5/ Reduced the width of his lower arms
6/ Gave the crotch armour a similar treatment to the shoulder pads
7/ Perspective of feet
8/ Decided I preferred the high neck feeling (More robotic)
9/ Decided I preferred the high eyes
So hopefully that highlights some of the problem areas. No perfect fixes just ideas and illustrating points.