The card market could be improved by adding one or both of the following:
1.A market where a player can put his own cards up for sale, but not in an auction format. A player would put a bunch of cards up for sale, and then he would select how much he wanted to sell at one time for a given price. for example, I put 27 Fugitives from Justice on the market, and say I want to sell them in increments of three for 15 credits. Then whenever another player wants to buy them, he can come to me, give me 15 credits, and get his three FuG's. It would be so much simpler that way.
2.A shop owned by the server where people could go to buy specific cards using either real money or credits.