This looks promising. Great job.
I'll leave you two side reference shot that should help you better model the head and also improve the textures from the sides, specially removing the "shadows" front cloning creates on the side of the nose and cheeks.
top notch for texturing:
https://cdn.vox-cdn.com/thumbor/K_zaUD2P3houilsbXM0twbIyJ0Q=/0x0:5184x3456/1200x800/filters:focal(2178x1314:3006x2142)/cdn.vox-cdn.com/uploads/chorus_image/image/65430837/AP_19281836947254.0.jpggreat for model reference:
https://media.gettyimages.com/photos/nico-mannion-of-the-arizona-wildcats-looks-on-prior-to-beginning-the-picture-id1203247073?s=2048x2048this last one can help you improve the texture of the eyebrows, cheeks, beard, nose, forehead, hair, because it has way better quality than the one I assumed you used. He is smiling so it isn't great to start with.
https://www.thestepien.com/wp-content/uploads/2019/04/0sEK1_Ng.jpegWhat I sometimes do when I have a great smiling reference is do a front capture of the model in blender with my texture (as big as possible), then go into photoshop and slowly replace each part of the screenshoted model (eyebrows, eyes, beard, hairline, etc) with my texture with the parts of the high-quality smiling photo.
Then I go back to Blender and use this modified screenshot as my background image. You have no longer to edit anything as the "model" is the same but the texture is now way better. I just project the duplicated UVS from the point-of-view into the modified model and adapt it.
I am not sure I explained clearly what I meant, feel free to ask me anything if you didn't understand it.