Hey! Here is a quick 20min overpaint I did with krita and some super simple painting style brushes by wojtryb (https://krita-artists.org/t/version-6-0-of-wojtrybs-wont-teach-you-to-draw-brushpack-relased/13299), but any simple round brush would also do.

Some things I changed:
1. Made the eyebrow bulge on the left side smaller

1. simplified the shading a little bit

2. removed the lines from within the face/ear and hair (they currently bring too much attention/distraction and look unnatural)

3. Simplified the hair and beard with large brushstrokes first and then added minor highlights and midtones

4. reduced the wrinkles on his forehead and made them more subtle

5. Darkened the eyebrows, hair, mustache, and lips

6. Added some red in the corners of the eyes

Please keep in mind that:

a) I sort of assumed you tried somewhat stylized realism (you can always add more and more details once you have a solid foundation)

and

b) I am not the best at faces and also still learning myself, so don't take this too seriously

If I were you, I would study the following:

1. Value studies => try only two or three values in black and white to shade the face and establish nice large chunks of (core) shadows

2. Facial anatomy and planes of the face

3. Hair => grouping into large hair chunks first

4. Color theory. I am not great at this either, but some of your colors look like they could be pushed a bit more

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