Personally, I don't think limpets should even have a reasonable limit.
We can fit 10's of thousands of point defense missiles, yet each limpet is apparently a goliath given the (1) per ton rule.
Limpets ought to just have a large 'ammo' pool like point defense once you've bought and installed the correct control module, in which case limpet ammo restocking would be automatic when restock ammo in stations, or have no limit as they should be re-usable, not one and done.
If they are indeed robo-drones that require (1) ton per 1 limpet, they ought to be rechargeable/reusable - so we'd buy as many as we can max control - e.g. have controllers for 12, then we'd need to buy 12 and use (12) tons - seems fair enough for reusable drones. But completely nonsensical for one-and-done throwaway munitions when clearly examples like PD exist.
As devils advocate, however, I concede that if whatever bizarre ED-physics/technology mandates that common-sense small things like docking computers and life support need to be ginormous installations, then I suppose that same limit would say all the miracle technology of 31st century ED-verse can't make reusable drones and limpets must be gigantic, one use only 'missiles'.
