Beauty – only average?

By chance a 19th century British scientist found out that superimposing several faces on a photographic plate resulted in a especially attractive face. The rediscovery of his principle in our days marks the beginning of modern attractiveness research.
But is beauty really only average? What other factors come into play? What does beauty have to do with having a baby face? What is the „certain something“ that makes an agreeable face a lovely one?