I have now settled in to fairly standard lighting techniques which seems to serve most purposes. Thought I would share this, mainly for the benefit of beginners, although comments from others about how they do things better welcome.
Step 1. Place two distant lights with shadows on, facing from the front angle 45 degrees approx off each side off the centre axis. This ensures all front lit.
Step 2. Place a distant light with shadows on at the side or slightly to the rear. The purpose of this is to illuminate the contours. Looks good with muscles for example.
Step 3 . Turn all distant lights down to about 60%.
Step 4. Place a spot light on the face, usually no shadows at about 50%.
Step 5. Do a render on the screen to see how it looks. The shadows add a good 3D effect but some parts may be too dark so add in a spot or point light at around 50% to fill in some of the shadows. You want a graduation of light and dark but full white or black is usually best avoided so balance your lights to avoid this. A bright edge effect can look good and sometimes full black shadows heightens lurking evil but most of the time avoid this.
Further steps. Repeat image with advanced lighting such as Lightdome 2 or IBL. These tend to give quite flat lighting effects but they show up the surface detail well. If you now blend this with your original picture you have the best of both worlds - exciting shadows and good skin texture.