It might be possible to reduce or remove the 'stealth' trait from stones. Poisoned throwing knives, on the other hand, must stay as they are otherwise both the "Assassin" and "Bartolomeu" storylines will break - both rely on you being able to kill soldiers with poisoned throwing knives at certain points in the stories.Maybe, guards should be made more resistant to stones as well?
I'm not sure what can be done about that. Perhaps the answer is, if you really want to spend your time farming like this, go ahead. Personally I'd rather spend my time looking for enemy ships to plunder.Here, you can see how I get a lot of jewelry without penalty or resistance.
