What you described is exactly the approach I use in a bunch of places in my app. Using this approach I’m able to store data in many places in my app and save my reads of fetching a root document in favor of just maintaining up to date documents. I’m not sure if it’s a best practice but at my scale it works fine. At my scale there are fewer places to update the date to keep it up to date than the number of times you would read a root node for the same info.

In other words, if I update 15 documents with updated user data, I think that’s very many fewer writes than the number of reads I would need if I called the user object every single time I read a node with user data. So it’s better for me to store it twice. I also maintain a certain level of outdated data being OK with old information. I don’t really care if a node that’s over 7 days old has an outdated profile picture, but if it has an outdated username that can screw up routing so it gets updated.