Wait a minute! If I pump them directly into drawer controllers instead of intermediary chests, that might do that totally automatically!I cannot believe that didn't occur to me until just now! I'm way overthinking it.
It in my pack, but I don't even know exactly what it is there for yet. I'll tackle that stuff a bit later and I'm sure it will help me make it more efficient.
Lock the drawers with the drawer key. It wont put any items into blank spots if the drawers are locked. Then just manulaly add the new items to the drawers as they come in (and you dont have to unlock to add to a blank spot).