If I'm getting ready to make a working protype and am designing some fairly basic cards, while still trying to get a good sense of design, color, icons, artwork, and so forth... should I also be worrying about the size of my cards? Because right now, the layout of my card design could really benefit from the cards being a little bigger than the standard deck size of 2.5x3.5 inches. Should I make them as big as need be (within reason) ? Or stick to the standard size and make it work?
Ultimately I want to try and sell this idea to a game company. If that doesn't work, I might go down the self publishing route. Just in case that makes a difference on the answers.