The reason I took the value of that shadow at the tip of the lips/under the cheek significantly up is because now it seems like the cheek is caving in, and flapping up again for the chin, which I personally find unattractive. I think the nose is a bit flat. I can't exactly go on and on with critique because I'll be basically describing my edit, so that's redundant.
edit: actually a pertinent question in the latest edit is... where is the lightsource coming from? I get that it's mostly washy daylight, but still, I am now confused. I thought it was on the top-left when I edited, so I added the nose shadow, did the edge enhance on the thing between the nose and the lips, but now... it's a bit blanket-shaded.