Ensure no unfiled (dangling) photos

As I move further and further toward a paperless way of doing things, I find myself taking pictures of everything including important documents, screens at trade conferences, my drivers' license & passport & other legal docs, etc. In order for this to work, a robust filing system is necessary. My basic problem is that when looking at my Camera Roll, I cannot tell at a glance which of my photos have not yet been properly filed into a folder.

To illustrate, imagine a pile of unrelated hard-copy documents sprawled out on the floor. If I want to file all of these docs away in topic-based folders, I take each doc and place it in the appropriate folder. As new docs come along, I can see these loose docs on the floor and realize at a glance that I need to file them away.

However, the way Photos works, it is as if I make a copy of each of those loose docs and put the copy in a folder but the original remains on the floor. Thus, the entire pile of unrelated docs (originals, that is) always remains on the floor and I have no idea which of these docs has ever been filed or not.

That's my problem. I've searched high and lower for a remedy, or even another user expressing the same need. In the past, when I haven't been able to find anyone else asking the same question, chances are good that I'm not using the functionality as it was intended. I'm okay with doing it a different way (even if non-intuitive to me) but so far, I can't think of a solution. Help please?