The skin is perfect. The little details I could put a throwing eyebrow on it is the cuts onto your character, if they are just made then they could be this red, if not you have to add some black in it for the dryed blood.
You could ad as well some little, micro blood vessels onto the cheeks, nose and chin, since your character’s skin seems to be thin and old. Please remember that the ageing skin tends to loose its fat, and so to become a bit more translucent. 
Touches of dark blue/indigo would be great just under the eyes, for the eyebags.
That was my two cents… Please, post some details about your techniques ! 
I’m looking forward to the final result !
Bye !