One might think headshot photography is a monotonous operation to shoot one after another of people... and get paid for pushing buttons. But that's exactly how photographers without brain would operate, and their website portfolio is not very exciting to me, even if hundreds of beautiful headshots are presented to demonstrate their experience. Good photographers would study the looks, style, and personality of individual client in a few minutes of conversation and make suggestions for the clothes and hair styles, and chose everything photographic, including the background. This type of photographers are rarer, but they usually have smaller but interesting portfolio and their websites often have insightful comments and suggestions. One such photographer I came across is Kaizen Photography of Los Angeles (http://kaizenphoto.com/). I don't know them and I never spoke to them; I merely looked at their work online.
 
In particular, I found this headshot to be of interest:
 

 
This headshot uses a simple but pleasing color arrangements (blue top and eyes in contrast to warm skin tone and orange hair), although the blue is a bit intense. It is also shot against the bright window, something that's not commonly done.
 
Indeed, this was interesting enough for me to try it myself. I added a new element to the work of Kaizen, though. These are two examples of headshots that I shot against the city view out of the window in my studio in downtown Boston. What I did differently is to change the color of sunlight.
 
P.S. the word "kaizen" is a Japanese word for improvement.