Looking pretty interesting. Some thoughts:
The red on the collar is so intensely saturated in contrast with the surrounding colors, it throws everything else around it away, stealing the eye's attention.
I'd seriously reconsider sticking with the original facial features, they're more original and interesting. The latter looks like your usual "bad guy" face
Those hands are going to be complicated... right now where the fingers entangle, they're a bit confusing (and have been so since the original concept).
Arm anatomy - see if you agree with this edit:

(mostly making the muscles follow the forearm twist, ignore my adding mass or definition, i know you're not going for that. Also, check my shoulder/collarbone construction).
For some reason, i find the shaded part of his left inner thigh really interesting to look at, like it has lots of depth...