I guess what I had in mind was "arbitrary data" lol. Like if it's content addressable and the remote source is still alive, whatever may be at that hash is what the data for that "file" is.

I would think this would allow for being backend-agnostic. As long as there are bytes to be received from that address, bytes ye will get.

But I am pretty green on your whole system here so there might be plenty of reasons that wouldn't work? (MIME types come to mind immediately)