I would like the gun from the beginning of the game back as an exotic , because the description of it did hint that it was a special weapon, so give it a name like "Guardian's Guardian" or something. Give it a perk that helps the guardian when they get to low health, and one that helps to avenge fallen guardians e.g. Enemy that killed guardian is marked on hud and the guardian gains 50% more damage for a short time after getting the kill. But keep the look the same.