I remember reading in an update summary here on this app not too long ago that said that the drop rate of the Vanguard Ghost Shell was decreased. However, out of the last 7 or so nightfalls I have completed I have gotten the ghost shell everytime but once. I'm a 335 hunter so a 330 shell does absolutely nothing. I think it's time to decrease the drop rate again.
-
When Omnigul was the Nightfall, I played it to completion with random people at least 30-40 times. I shocked me how many times I saw ghosts drop. Ghosts should be something additional that you're able to get, like after completing Challenge of Elders.