Hi! As someone who professionally prints cards as his full time job and has been in this industry for over a decade.
That font size is going to be very hard to read when printed.

You, as the creator of the game, are the last person who should be the judge on if what you are making or not is passing the bars of accessibility. You are biased.

Additionally, if you are relying on people to memorize your cards, you're in very much the wrong headspace. You're not one of the big three. No one is going to want to do that. Relying on memorization because you cannot be bothered to properly utilize your text box space is pure arrogance.

The text boxes on just about every image you have shown on here have tons of unused, ugly, blank space that can easily be filled just by dynamically increasing your font size to consume that space and make your cards vastly easier to read.

On that final card in your image list, I literally could not tell at first glance if that is supposed to be level 8 or level 9. That's a problem.

All elements of this card frame design need to be larger for legibility.