Preview Shots

Put the review-worthy images in front of the user in a single Preview window they can flip through.

Workflow

Curate the set — the images that answer "is this right?": the just-changed or just-blessed baselines, the integrated result, and the reference image when there's something to compare against. Don't dump every PNG in the folder; pick the smallest set that lets the user judge the change. If the user named specific shots, open exactly those.
One window — open them with a single open -a Preview <path> <path> ... call. One open invocation lands all the files in one window with a thumbnail sidebar; separate calls spawn separate windows.
Caption them — list one line per shot (what it is) so the user knows what they're flipping through.