If a stack-size over-ride has been set, I would like inserters to wait (forever, if need be) until they have exactly that number of items, before activating.
Failing this, I would like inserters to remain 'aware' of the contents of inactive furnaces' contents, if they contain 1 stone, or < 5 iron plates, and only pick up an 'appropriate' ore.
Reason: This would mean I could build a single array of furnaces, and run all my ores through it without it jamming. It's frustrating when I set an over-ride of '10' on a stack inserter, and it delivers, say, 8 iron plates to a furnace. It's painful when it then picks up a different ore, and requires manual intervention before it will work again. I want to be able to set a stack over-ride of 10 on my inserters, and have the array handle anything and everything. Please
If this change would break existing factories, an extra setting would work just as well - maybe individual settings for min/max?