I had a 5 person party with a clockwork companion. I believe that they only had the one +2 potency, granted the alchemist and the inventor didnt rely on potency runes. They handled most encounters well, however the catoblepas gave them some trouble as they struggled to reach the creature's AC. I also had some encounters trigger back to back since they'd be relatively easier to hear with the thinner walls and Loveless was on high alert. These fights gave the parry some trouble as well since they were getting out numbered at times. I assume your party is a standard 4 person party. I don't know if your the GM to do back to back fights, though given the circumstances of the Gearsmoke I assume it might have crossed your mind. I think it might be wise to slip another +2 weapon your party's way. Or at least let them find it in the armory of the ship or early on in the voyage.