Sastian,
Just a comment on your background color poll, and over-all design:
As someone also working on their own deck, I too have asked for opinions on a few issues; before I realized that I would only be truly happy with the deck I'm creating by following my heart for better or worse. And that way, if my deck succeeds, I will truly be personally proud of it.
In your case, no matter what input you have from others, I hope you will also just follow your heart too.
Based upon everything you have shown so far, I admire your work greatly.
And rather than advise you on colors or design, I'll just say that I will pledge on your cards, and be very happy to receive them in whatever colors and final design you personally are happiest with.
Please yourself first, and everyone of us lucky enough to get a deck of your cards will know we are holding a piece of your imagination in our hands.
Thank You for Sharing,
Will Hart