Sometimes newbies want to play a rt game but can't because they are at their limit. I believe it would increase membership if premiums were able to buy credits and use them to purchase a speed game for a freemium. It would be good if these credits were cheap so they could be freely used to encourage people to join conquerclub without putting a financial burden on the premium member. If the newbie deadbeats the credit should be returned.
EDIT: Shino Tenshi made a suggestion for smaller memberships, like a dollar to play for a day, or $7 for 3 months.