The skill to retouch a photo of a person and still make it appear natural is something that takes time to develop. Every time I pick up my graphics tablet pen, I know it will be as much of a skill as a learning experience.
I originally used to stick to the doctrine that photos of people should be left as they were with perhaps the most basic of colour balancing. This suited when I didn’t have a lot of time to spend on working to remove blemishes and such.
Of course, now that I have less time, it seems only appropriate that each photo I produce should be photoshopped carefully. Non-permanent blemishes are blended away and unflattering shadows are softened leading to a clean, yet natural finish.
Give me a shout if you’re interested in some Digital Retouching.