First of all, this is a great plugin. It actually killed two birds (co-authors and guest authors) with one stone for me in setting up a new WordPress site.
I noticed that this plugin registers 4 new image sizes seemingly for potential guest author avatars. Unfortunately, this is happening for all the media I upload, resulting in thousands of images that will never be needed.
Is there a way to turn this feature off in the plugin, or to only have the plugin create the images for guest authors that may very well need an avatar?