Likeness is a weird thing. The way we see ourselves and others is entirely subjective. Nonetheless, if a drawing doesn’t look that person, it’s just wrong. No amount of subjectivity or superfluous detail will hide this.
I think the secret in capturing someone’s likeness is getting the spacing on the face right. If I get the distance between the eyes right, or the length of the nose the chin correct, then I’m pretty much halfway there.
Of course, if I really capture the subject’s spirit, their personalty, then by Gawd, I get more than a likeness, I’m characterizing their effervescent soul.
If I were to go by the photos alone, then I’d kinda be missing the point.
When I draw you an avatard, I like t’ just take a look at your pics on facebook or what-have-you for a few minutes, and after that, I’ll sit down and do some sketches. Then, I’ll draw you from my sketches instead of your pics. That way, I don’t get bogged down on the subtle details on your face that no one really sees when they look at you, anyway. This is why a good caricature will always look more like you then YOU look like you.
I guess you can be the judge of the similitude.