If you use a small amount of energy from your batbox, your generator will start up, recharge it, and then waste the remainder of its fuel cycle. It would be nice if you could connect a redstone signal from the batbox to the generator to inhibit its startup until the batbox is low/empty.
It looks like the batbox has a nice ui to configure its redstone behavior. It would be nice if rather than outputting a full on signal when empty/full, it could output a signal whose strength was proportional to the eu contained in the batbox.