Someone else might have already thought of this, but I think that its important, so sorry in advance if you've already veto'd this before.

So, whenever you integrate Storage drawers into another sorting/inventory system you run into a problem when removing all of a single item from the managing system. For instance if I'm using Simple Storage or AE2 and I pull all of my stock of item X from the interface, the Storage Drawer that held X becomes denatured. meaning the item on the front of the drawer disappears and it no longer filters for that item. So I propose an upgrade that reserves a drawer so that it holds the filter even when it is empty.

I found a post about this right after I posted mine.... sorry for the inconvenience