Add used by in content usage in AGOL. It would be great to have a list of everything that accesses a feature layer, web map etc so you know what needs to be fixed if you make changes or delete an item in AGOL. I see it a being something similar to Oracle's "used by" that lists out what is accessing the item. This would help in knowing if others are using your data and allow you to follow the trail to see what they are using it for. It would also allow you to know if you can delete or change an item safely.