Our different websites are overwhelmed by having everyone else's photos and this does open us up to having a photo that shouldn't be shared ending up on the wrong site. There should be a way to have a photo applied to a specific site and given permissions.
I have also been requesting this feature for a while. Composer currently has the option to restrict stories by utilizing the restrictions/distributor/sites concepts in global settings, connected to the squads acces to a site given in Permissions. So the concept works, and should be introduces for photocenter, galleries, lightboxes and also videos as well.
The permissions design was presented as a core feature of Arc and an important reason why we chose a multitenant setup for our 5 very different publications. This must be improved!
The inability to sort by only photos in the Photo Gallery by our station is a big slowdown to our workflow.