The down side it very powerful cards (which there always is) will be focused on and have relatively higher print numbers and there will be a supply imbalance.
That being said with them axing all in print reward cards rather then allow them to finish they have knowingly done the exact same thing.
Rather then DEC burn what about burn 3 cards of same rarity for 2 random cards of same rarity? This would likely be too expensive for profiteering but allow me to get rid of all the life cards I don't want as I don't even have a life summoner for example, and speed up leveling the cards I do want.