IMO it's possible to use just the face-morphs to make real life characters, I have made a lot of faces (more than 50) based on real life people just using the dials. I only use Zbrush for some specific details like noses. You're right about the eyes, but the nose and the mouth of the basic V4 are also out of propotion, so the first dial I use is the face size to make them smaller and more realistic.

 I think the biggest problem is that people are afraid to exagarate: real people have big noses, or a big chin or an ugly mouth. That are the features that make a real character. Subtility is not always the answer. The age-dial is also a big help, it gives more depth to a face.

What important is to know how to use the dials, how to achieve just that specific detail you want. And that is just a matter of trying and trying and trying. Sometimes I spent weeks to get the face I want, sometimes it's just a matter of hours and sometimes I completely blew it and have to start all over again. Over time you will get a feeling how faces are built and which dials you have to use.

-How can you improve things when you don't make mistakes?