I may be a playing card newbie, but I am a professional graphic designer with over 13 years experience. I love the back design, and I agree with one of the comments about possibly some embossing there, if the budget permits. Maybe some foil in the tuck would liven it up a bit, but overall I like the minimalist approach. The AoS is a bit weird for me - but I can think of a ton of deck designs that have some weirdness to them. It's what makes them stand out in a crowded sea of decks out there. As far as the use of white space as it effects fanning, I think this is a non issue. If the artist posted this deck as a fanning deck, and was marketing it as such, maybe you'd have an argument. But this deck is a clever artistic take on a fresh idea. Overall, I give it a solid A.