When I moved from Pocket to Memex, a few years ago, I inherited of a Space called “Read Archive” which I now renamed “Archive”.
I haven’t used Pocket since but I remember that you could archive a saved web page and that it would put it apart from the non-archived pages. So that I could browse all the pages that I had not read yet and decide which one I should read next. I was using a Pocket client on my Kobo e-reader, so that was very practical to be able to browse only the pages I had not read yet.
I’m not sure exactly how this feature could be implemented but basically I just need to be able to exclude a Space from search, in this case that would be “Archive”, so that I can just browse/search the links that are not in that Space (not archived yet).
I guess either a new Archive feature could be implemented or just a new search feature that would allow for similar results.