Hello!
I've been exploring ideas these past two days for an Egyptian Revival art deco styled deck. This will be the first deck I've designed. So far I have the basic composition for the back of the cards but am not ready to show any of the other elements at the moment. Lots to learn!
If you plan to print these back designs without a border around them, be prepared for a few possible issues.
1) If you print with USPC, they're known for trying but not always succeeding to make perfectly centered die cuts when punching out their cards. If either design wasn't cut totally centered, there's a good chance you'd end up with a one-way back. A white border can hide this to some extent. Alternately, you can add a border in a color that you choose as your "background" color - you'll have to deal with a different issue (see #2, below) but it's less likely to appear one-way to the naked eye and still look attractive like a print-to-the-bleed card.
2) If you are indeed going to print into the bleed, the cards will look really good when they come out of the box. Over a short amount of time and some usage, however, the ink will chip, exposing the white paper beneath and make the card edges look shabby. This happens to white-bordered decks as well, but because the paper is also white, it tends to be less noticeable without a close examination, closer than most people bother with. It's unavoidable, but some artists/designers say "damn the torpedoes" and do it anyway because it really does look cool straight out of the box. You have to decide if you're one of them!
I do like that they aren't typical designs. Sometimes it seems like there's only a few basic patterns out there and that nearly all card backs are designed based on these basic patterns, like the circles and border of the Bicycle Rider Back or the quadrant pattern of the Tally Ho Original Fan Back, etc. Yours is more unique, and in a good way. There is a basic single-circle radial center pattern to it, but there's so much more going on in there - it makes the design more appealing.