I would like to point out that, assuming that this leads to an increase in the price of cards, then criticism about the size of the discount becomes less relevant.
i.e., the ~50% discount (based on, say, the price of 200 x $0.01 common cards [+ vouchers]) becomes zero if those card prices were to double.
Personally, I like the idea .. but would increase the burn & vouchers required by an additional 50%.