Yeah, I'd go along with everybody else; you should study the face a bit more. If I were you, I'd start with piece head on..and when you get the hang of it, move to a profile...and then, after learning those two, try the angle you're going for now.
Of your newest four, I'd say the second is on the best track. You seem to be adding too much head behind the chin, if that makes sense
. Three and four are suffering from misplaced chins and mouths.
Either way, practice makes perfect, so keep pixelling!
