This is very commander and loadout dependent. I would start with a full hold of limpets and see how many I typically jettison over the course of several runs. If I end up abandoning a large number of limpets, I would start decreasing the number I take with me (always with some marginal for the eventual misshap). I typically run with 140-150 limpets in the 192+6 Python.Yes you should have around 90% of your cargo space loaded with limpets at the start of a mining trip. It can be frustrating if at the start you have to ditch limpets to make cargo space then run out of limpets at the end so always leave a little room for the first few loads.