Looking cool bro!
Some nice shading/highlight work going on there.
My only main critique would be that his arms look like the elbows are on the front. I'd suggest maybe having his arms slightly bend inward a bit to help with that.
Ie,
Now:
......O
....|.|.|
....|.|.|
......|
...../.\
Fixed:
......O
...../|\
.....\|/
......|
...../.\
(only with not so much of a bend...that's just to illustrate the direction I'm talking about