Trying to find a perfect design template is like trying to find the right way to sit on a bicycle with the seat missing... I don't think anything will feel comfortable. But I am trying to find something generally visually appealing that works with the theme and concepts of the game.
Tonight I was able to remove my elementary art background and replace with some textured imaging to help highlight the cards a bit. Not sure if that's the best idea, but it does stand out a bit more than what I had before.
Attached are some before/after pics to compare. If I do decide to stick with the new design it means going back and reformatting everything I've already done, but I guess that's part of the fun isn't it!