Zanzarino, I've seen a lot of original card ideas on the card ideas forum, as well as generic ones. I like to put a lot of thought into cards, and as such:
What would you give as advice to card makers that have a solid grip on the general rules of card design (keep it simple, use the proper format, etc...) and are ready to begin designing cards that could potentially make it into the game?
Many thanks, and I look foward to the new and interesting cards that continue to come ingame.