Over forty years of experience have led me to choose clamshell lighting for my headshots when doing a large number of people for an organization.
The main reason for choosing this lighting setup is that I can have people face left, right, or straight on without moving my lights.
You can choose different backgrounds with this setup. Right now, my preference is white or light grey for a set.
Here are some recent headshots I did with a muslin grey background and white background using the clamshell lighting technique.