Hey joshB. Keep up your hard work and don't stop posting man. Your faces are coming along.
Im just a begginer and when I first started posting, people told me what Im about to tell you. The range between your darkest value and your lightest value needs to be bigger. Thats darker darks and lighter lights yeah? The faces you have done are good but their values are all kinda mid range. If you have a mid tone across the face and then made the shadowed areas a little bit darker and then used an eraser to highlight the lightest points, those images would pop off the screen man.
I look forward to more.