I mean for layout think where people's eyes are drawn to immediately which can be influenced by art but also how people tend to read.

I think there would be a lot to gain from thinking about why say a magic card is laid out the way it is. Then perhaps extrapolating some general principles out of that.

Think about the most important pieces of an info for a card (cost and main effect usually) and have those be easy to find, bold or just where peoples' eye first fall to. Another thing magic does (which it's pushing the boundaries a lot on now) is centering the art rather than the frame. So having minimal but still flavorful frame elements would be a good idea too.