in my eyes it would be better if you sell items, effects or what ever
special made for servers (not global) instead of cards which work on any server :O
like on zod :
you can add something that let you level faster for some days
i think nobody cares if someone levels faster than other people because in the end all people are same strong because of the level cap...
there are people who have work to do in rl and if they get money there they can spend it for items like this
because they dont have so much time to play
or like they said before a key to a special dungeon where old weapons drops in new colors or with new skins :O
on other servers you can add different things so nobody has probs with effects which works on some servers but ugly on others
but pls talk to the managers of the servers about this before adding things
i have no prob to pay for special things in a game which costs something at all :O
in wow its the same with the trading card game there you can get special things like a turtle mount too...
i can say so far that i will add places for special items on symphonia