Currency exchange improvements

After using the exchange for a while here what i think should be changed.

-Gold cost scaling is insane, i understand that the fee is needed so we dont turn a game into path of exchange, but right now one order for me costs more than 500k, its too much. As soon as i started using a lot of currency, gold became a problem.
-Alva most of the times finishes the order even tho you still have currency to exchange. And she does not return gold thaty was wasted. I dont understand why this is the case.
-For some reson taking currency from alva with cntrl is way slower than from a stash. It has weird delay and takes forever.
-Make it possible to put the entire order currency straight to the stash. So we dont have to first take it from Alva(again very slowly) and then to stash mannually.