So basically what you suggest is turning reward cards into a web2 version of the game. I mean, I would like to see that but with ghostcards not with reward cards.
What do you think about the limited unlock amount I suggested in my other comment. I think that is a good in between, where the majority can just use them as soulbound rewards, but if you put DEC into a share of the card value, instead of infinite print, you probably have the best of both worlds.
RE: Soulbound Reward Card Proposal - Immediate and Ongoing Accessibility