Hi,

First off that's a cool bust, and I hope you'll end up with a good looking piece when you're done

Now for my 2 cents,

I have been painting 28mm models for around 12 years now and started out with enamels on 1/72 aircraft before that and I must say enamels would not be my preferred choice of paint for this kind of project, acrylics is far easier to work with IMO  But my pointers should be useful anyway.

First off I think the eyes are a bit too large, making them a fraction smaller would help a lot. And a really neat trick is to make sure the white in your models eyes is outlined with a dark shade as this helps define the eyes better, in this scale I'd suggest a dark tan/brown colour referebly mixed with the darkest of the colours you use for the skin for a more natural transition from the skin to the colour between the eye.

Secondly skin will look very doll like if you don't add areas of redish or purple tones (very thin washes are great, or simply mixing them in your basecoat) for areas such as the lover lips and under the eyes as very refined colour tinting in areas which have more delicate skin and therefore more bloodflow will vastly improve the "life like" feel of the model.

And then lastly the stubble will benefit from a slightly more rough approach than the rest of the skin to simulate the roughness that stubble leaves. And shading is very important to make stubble stand out.

To show an example of what I mean here's a picture of a model 'm working on at the moment, it's a 28mm model but should underline the general feel of what I'm saying

[ATTACH=full]34134[/ATTACH]

Hope this helps a bit