I have an idea that would help teams see at a glance when a section is updated or new content is added, via “notifications”. This is commonplace and user-friendly. I’ve included a sample screenshot.
This is especially helpful if you have a lot of content. Another ancillary option is to allow end-users to subscribe to get notification updates by email if content is added to a section or content is updated.
One other note here: I would recommend the notification be setup as a manual process so the editors can select which/where to set a notification update. As you know, many groups hit the produce button for a shelf and all the content is updated so it can’t be based on the timestamp of the file but as an example if I wanted to let end-users know I have 5 updates or new content in a section, during the production process, I set that section to 5 (as an example).