I suggest in time of struggle to take few min and gather some useful reference , you could start with an actor or someone who have heroic features or comic superhero or even something idealized as Loomis head proportion guy + also check robust or masculine skull
Structure is exactly what you need , everything else will be pointless if you don't have structure, that's why I added skull in the list above , Loomis could help with overall proportion and feature placement also check for planes of the face referenceFew suggestion about how you could proceed , if you mirror front view…