If I mine copper with 26 electric mining drills a normal transport belt will be satisfied (regarding http://referencio.info). If the ore patch is greater than 13x2 drills the mod still places those. Any way to reverse the output direction or so to prevent "useless" drills?

In theory it could, it already does the belt throughput calculations.

I can't really see myself using this though, when would you turn it on? (with how I play this could be useful in the early game, but I don't have bots anyway so just place by hand. By the time I have construction bots I would rather just put miners everywhere so it keeps working when they start running out.)