Add a button below “update to cheapest” in the drop down menu that will automatically update all cards in a deck to have the old border version if that exists. (“frame:old” in scryfall parlance)

For a project I’m working on, it would be very useful to have an “Update to Oldest” option, which woud also fulfill your goal.

As a fellow retro fan, I can imagine how much time this would save on building from scratch. Love it.