If they're as frightening as the demonic ghosts in the broken ship in Oblivion, I'm all for ghosts. Only thing is, would energy weapons be able to disintegrate them since they're already dead? Feral Ghouls fall into the same category as ghosts I'd say, though ghosts aren't physical beings.
You found those ghosts frightening? I guess frightening maybe in the sense that they took a lot of damage to go down, but other than that? Not really.
I certainly don't want ghosts in New Vegas that can be
killed. I mean, come on! That would introduce even more insane questions than there being visible ghosts in the first place. Are you planning to stab them to death with a Throwing Spear, since they "fall into the same category" as Feral ghouls? Ferals aren't zombies, they are living, breathing, human beings that are brain damaged and insane.
Vote No to pseudo Vampires, Zombies, and Ghosts in our Fallout!