These are all drawn from a book called Face It: A Visual Reference For Multi-Ethnic Facial Modeling I was very happy to find this reference, it has a lot of photos of a variety of different looking people with front, both profile views, both 3/4 front and both 3/4 back views for each person as well as some expressions.
I'm looking at my general model as I draw these, looking to see how they deviate from it and looking to see how I can revise the model to work better. I used a circle template for a bunch of them to try and keep the sizes consistent, and the last set was drawn with my most recent 3/4 general model actually under paper. I was specifically looking at how to define the side plane the silhouette of the far side of the face.
