He's looking pretty good. Just smooth out those splines around his mouth (and you have a gazillion of them. Maybe might be worth cutting out a couple lines of them or something) and fiddle with the proportions a little and he'll be perfect.
Proportions: okay, first off, ears are never that high on people. The tops are usually level with the eyebrows and the bottoms with the middle of the mouth. They're always right on the jawline, so it'll look wierd until you tweak those splines around to accomodate them, but there it is. Cheeks have a concave line from just above the nostril to the edge of the mouth and only at those points curve into a circle; a perfectly round cheek doesn't exist. Pull those control points that connect the cheek to the upper part of the nostril out a little and you'll hit two birds with one stone, as the nose won't look so thin. Eyes are set back in sockets; you don't need to actually show those, but the nose's bridge would be out farther and the eyes back in. Actually, I'd suggest finding a profile image of a person to use as a rotoscope while you tweak; you don't need to find someone exactly like the character you're modeling, but just the proportions would be helpful. Especially around the mouth area: it's hard to tell from front-on and 3/4-view, but it looks like the lips are on a level plane. Mouths actually curve back at the edges; think about the curve of the teeth and jaw. They also puff forward pretty significantly at the middle - shine a light down on your face and look in the mirror and you'll see a shadow under your lower lip. Again, a good profile rotoscope would be invaluable here. Pretty much all of those wierd creases around the mouth and cheeks would be solved by tweaking it in profile view.
Hope that all helps.