I looked at all of the photos that you up-loaded, and noted that most were 100kb or so. Something you may try, is to upload a little bigger file size of the pictures. Maybe around 500 kb for the individuals. Then when the viewer clicks the option box for a size of the photo, that the detail in the larger pictures is sharper.

I do not think it will slow down the load time for the people looking at the photos.

Another thing that you may try with one of the Albums......in the settings, you can restrict the size that the viewer will see. Maybe you only want them to see the Large and Extra Large version, and not the Originals.

The SmugMug program provides a lot of control.

Joe