You can export the skin in BodyShop then paint a face on it.
I saw it on a tutorial of making celebrity sims once.  They copy-and-pasted areas of the actor's face onto the skintone to make it look more real.
Personally, I understand what you're saying.  I don't want to download a skintone with eyebrows that are bigger than the ones I want to put on a sim.  
