When creating characters from human reference photos, it's best to use at least two photos (front and side) for the most accurate results.

This video shows a workflow for using side reference photos, but I find this process way too manual and clunky. There is no way to easily switch back and forth between front and side views, because as soon as you change camera angles, the model no longer lines up with the side photo image layer.

Ideally, the auto and/or pro head generation modes would have an option to load in up to two side photos as well, allowing for a more accurate head shape right off the bat, as well as a more detailed texture map (if my reference model has moles on the side of their face I'd like those moles to be projected onto the texture as well).

Of course this is a pretty big feature request, but I think it would increase the usefulness of the software significantly, and make me way more inclined to purchase the software (I am using the free trial at the moment).

I agree totally. Right now Headshot is really bad at getting reasonable profiles, and it surprises me that this is not already a feature. Or, alternatively, a 3/4 view, which assuming symmetry, generally gives a very good guide to total face construction.