Specific stared cards could be bought with gold; 1* = @100; 2* = @1000; 3* = @10000; 4* = @100000; 5* = @1000000; 6* = @ 10000000.

This would finally give a use for gold!
It would reward people who are actually online more instead of people who just pay!
Of course the selling price of cards would have to be redone ( maybe %50 of buy price?), to compensate for the change in gold's worth.
Overall this would give guild actual worth, as it's ment to have