the concept behind your wallpaper is very, very nice but somehow, IMO, it kinda lacks more elements to it. i wish there were more cards with their face up along with the 4 characters that you used here. doesn't matter it they don't have any character in them. so long as they're scattered around as well. would look nice if you added a faint/subtle paper texture since they're playing cards right? :D
anyway, these are just my suggestions. ^^v hope they help you out in some way.