Great video, looks very professional!

Personally, I prefer text for this type of content, so I particularly liked the small text boxes. ;D Also the "close-ups" eg. when cutting the cardboard were great. You feel a bit like being part of it and you are animated to replicate it. Maybe I would even add a point at the end where you can hear the sound of the device in operation.
One question I have: The mechanics is indeed driven by a servo. Is this "hacked" or does it go back to its starting position after each ejection of a card?

By the way, the trick with the wood to reinforce the cardboard, I have directly noticed. :D
I'm looking forward to a final video / article with the finished feeder.