The biggest issue with the game is the lack of PvP variety, I used to play this back in the EA days and I think people drifted away from the game for this reason, preferring the matchmaking of RTS and MOBA games. I would suggest adding more PvP variety that will allow newer players to practice with their lowly cards and have fun doing so (hopefully some day when there are large enough numbers we can get matchmaking). To get this going I propose a casual PvP non-ranked 3v3 and 5v5 maps