Well, this thread is old. But I have some ideas.
You could offer a way for players to gamble their credits.

You could take the total amount of gold in the game and divide it by the total amount of credits in the game or spent (..or bought,etc).
Example: 10^24 / 10^8 = 10^16 gold per credit. This would be a sort of gold to credit ratio for balance. You could figure out something to use this for.. (gold drain, etc)

The amount of gold you can get for trading credits could go up per level. More gold would help new players, I think..

It could cost gold to kill bosses, or do quests, or something..

Surveys would be pretty interesting. Algadon could do with some advertising. Maybe some incentives for 'voting for algadon'.. etc

Maybe there could be quests that cost rc to do? XD rc for clan bosses?

A gold lottery. random numbers. Just because..

I'm a noob.