The only thing holding red death back from being great is that it has a very short range. Considering that it is a pulse rifle and is a mid fire rate pulse rifle which can't compete at close range I think it needs some more range so it can fight in the intended range for this archetype of pulse, or it should become a high impact/low fire rate pulse so high skill players can get the two burst kills like back in the early days of vanilla!
Comment below why you want the buff so bungie can hear us :)
Edit: Yes, at launch the red death was originally a high impact pulse but they latter changed it to a medium pulse rifle. I personally preferred it as the low fire rate pulse rifle.