Here, i did my own edit to better illustrate what I meant.
While keeping in mind the color blocking (keeping like colors as grouped as possible) I divided his face into three parts from the light source, which is above and to the left, meaning left would be light, and right would be dark. Same respectively for top and bottom.
I studied the shape of his eyes, leaving the shadows in the same general shape (he has very sad eyes, that actor) and left a connecting line between them for the bit of browline where the nose divots to meet it.
I also opted not to give him a mouth, focusing instead on his prominent dimples. I also expanded the darks on his face to match the picture.
I eschewed some of the finer details along his face, like that shadow down from his nose to his chin, since they would confuse the eye and make the picture harder to read.
I hope this helps you along, I did base this on a prior edit.
(Also for the future, there's no need to x2 your resolution here, clicking on the pictures magnifies them as part of the site design so people can blow them up without quality loss!)
Note how it looks at a 1:1 scale, without magnification, that's what I usually shoot for it looking good at. Aseprite has a 1:1 scale viewer as a feature and I take advantage of that a lot as a result.
