The problem right now is that the exchange doesn't let people trade at the true value of Zen. With keys going for 80,000 AD right now, that makes 1 Zen = 640 AD. You like 10,000 AD more per dollar by selling keys than using the exchange. The root of the problem is likely inflation rather than the cap on the exchange. There…
I'd love to see some sort of reward tokens for completing foundries, which then could be traded for unique items from a vendor. Something like Glory or Seals in mechanics. Maybe only have them be awarded on longer foundries, to get people to play and write more involved ones. Even if the things you can buy are just green…