Very nice work so far,
I see what ya mean w/ wrinkles in the forehead
I would start with indenting where you want the lines , and inflate the forehead area around the wrinkles slightly , then just work with them slightly to make them more natural/noisey to give it that randomness of life feel
no two foreheads are the same thats for sure but i find puffing out the forehead skin around the wrinkles goes a long way for giving them form.
you can always deflate the forehead skin after you get the form down…
Jaw line is a little too rounded imho… but damn im impressed with the overall look of the model thats for sure.
doubt you’d see me comin up with those nice areas for the eyes… i really like that part of the model.