IT IS AN EXOTIC WEAPON, yet it's worse then Legendary Grenade Launchers, or even The Mountaintop, a Kinetic one, for killing red bar enemies. The damage increase you plan to do will not be enough for it, it will still be a far weaker option then Thunderlord, which is a great enemy clear weapon. Xenophage will not be used even after the 50% increase, it will be thrown away. Basically it should be a Whisper of the Worm level Exotic, especially with it's mission being rather hard, and also the fact that it really gives that vibe it should be like that. So in order to make it really feel like an EXOTIC POWER WEAPON, give it 75% increase in Damage in PVE, and increase it's base PVE Ammo.