Again, I agree with Clair's comments, especially about the extreme redness.
My guess is that this image has already been subjected to quite a bit of post processing, hence the artifacts that Clair is referring to. I would exercise a lighter touch with the processing, with most of my effort directed to adjusting contrast and balancing light levels (eg, foreground / background, bringing the viewer's eye to the face instead of the coat, etc.).
In the attached image, I've tried to illustrate the direction I would take this image, if it were mine. Unfortunately, I couldn't do much to improve the three dimensionality without spending a lot of time painting in shadows. With respect to the compression artifacts, there wasn't much I could do with them either, so the image still is a bit rough and gritty, especially around the mouth, but with access to the original, this would be no big deal. BTW, I also didn't want to spend the time it would take to remove the tree directly in back of the subject's head, but that's another change I would suggest (hopefully at the time of shooting, not afterwards).
HTH,
Tom M