The Last Word really isn't optimal in PVE, but it's a fun gun to use, and looks pretty awesome. My suggestion is to make the catalyst provide the Osmosis Trait, among whatever other perk they are tooling (likely pvp focused) Similar to Traveler's Chosen, this would open up synergies with the 3 Light classes in PVE. Personally I would combine it with my trip-mine grenade Hunter as it synergizes with Gunpowder Gamble. Would you find it useful?