I have a suggestion for the DEX if you aren't already working on it.  Can you make a way for it to automatically break the wallet's UTXOs into the correct size so that it will match the size of an open existing order's UTXO?
For example, if there is an open order I would like to buy, I would click on it.  Then, when I click the buy button, it would automatically break up my UTXOs to the correct size. 
Would that help orders fill faster?