Thanks folks [Crown, Tom, Andy, Nitsuarox and others] for your comments. Yep, if something seems wrong with the head, then there probably
is something wrong with it

. That's one of the problems of using an image [and not an actual real-life model] for reference -- you have to proceed by guesswork as far as dimensions are concerned. Thanks for pointing it out. Here's a second version of the LEGO man:

But even this may not be dimensionally accurate. I had a LEGO police officer toy as a kid, but I can't seem to find it...