Definitely not a waste of time.
I'm not sure how far you want to tweak it, but it has all the makings of something great. Like Robert suggested, a hair shader might help get it farther along. Also, I would suggest a slight change in lighting...if you haven't already, try changing your light to Z-buffered shadows (hair reacts better) with a slightly bumped up Map Resolution of around 2048 and use a Rembrandt lighting setup. Then, you can add a normal map, bump map, displacement map or combinations of the three for the skin texture to add pores, etc. Some specular in the eyes and a slight specular on the skin (I would recommend using maps for that as some parts of the face tend to be more oily than others) and then a slight SSS on the teeth (you'll have to experiment there but a start would be .45, .40, .35), and skin (1.9, 1.2, 1.0 for the skin) . I'll add some MuHair settings to try in the attached image.
Hope that helps.