Ok, had a bit of time spare (very busy working on my own stuff) so I quickly put this together.
I'm not sure what card size you are working towards. After finishing I measured this sample and it doesnt fit any of the standard card sizes :)
It's not far off the standard size for MTG Trading cards (63 by 88) - being 1mm real size off at either side. If that's what you're looking for then I can make a couple of simple ammendments to size it up correctly.
In all honesty, the perfect layout and size probably arent that important at this stage. Play testing has a habit of throwing up card changes that may or may not require a re-draft.