I think skill farming is fine. I mean, it makes sense that your crew might have found a weak drone floating around, and decided they could use it for target practice.
The best way to skill farm I had done, though, was trying to get max repair skill by bombing my own ship. I had stockpiled missiles through sector 7, and had a Small Bomb that I wasn't going to use, so I took that chance to bomb myself and get my 12-skill mastery Crystal crew
