They don't need any nerf, not even a slight nerf.
I know you nerfherders love to ruin anything good. You nerfherders had a shot when the game first came out. Unfortunatly the player base bailed on the game, so it's time for buffs, and for guardians to be strong.
It's time to stop balancing the weapons in favor of PvP. I am not against a good PvP, but the game suffers when Bungie tries to make the guns/abilities balanced in PvP.