Hi _ck,
welcome to
RP!!
Being more of a 'restorer', these kind of 'retouching' isn't really my cup of tea, so, please take whatever I say with 'a grain of salt' ...
Overall you did quite a good job, I like the colours and you managed to give a nice metallic look to the skin ...
What I would have done differently is:
Clean up the image more accurately,
'tweak' the shadows ... lifting them a bit for a start ... (his forearms are very, very dark and you lost details in some parts of the picture) ...
go easier on the contrast to avoid the 'blotchy' look ...
That said, retouching is very subjective ... so, your aim might be exactly the opposite of what I'd like to see ...