Just add mining and astrogeology to the skill requirements to fly one.
As it is right now, skilling into an orca is faster than an exhumer, which is pretty dumb, but if a player has spent their time skilling into a bigger and bulkier ship, then they deserve the benefits it gives.
People mine in orcas because it’s safer and need low management, but you can still be griefed by some random guy coming to shoot down your drones, or bump you away.
There’s no need for a new “mechanic” just because you have a problem with someone else making more money than you with less effort, or because you can’t easily blow them up without putting a good effort. 