Steven Zahm@ Kelly
The cropping is largely affected by the source image. Cropping for images in many such plugins will base the scale/crop on the center of the image. Because, generally portrait shots have the face nicely centered within the image. So, that said, the image you upload, the closer the eyes are to the center the better the crop will be.
Changing the size will not affect the scale crop, it only will make the image smaller/larger.
I do have a free addon which you can try out. It is creatively called Face Detect. Here’s the link:
https://wordpress.org/plugins/connections-business-directory-face-detect/
Be aware applying this is rather server resource intensive. So, I would recommend uploading images where the face is as centered as possible.
Hope this helps!