Anyway, I had two suggestions.
1) When dragons attack, the Guards yell "Everyone get inside." No one does. Instead, they all seem to have an aggession level of 100 or something and run into the jaws of certain death.

2) A way to make both the people who love their NPCs and the people who want ghost towns happy: A dialogue option for any NPC that is quest or service related where if we choose it, marks that NPC as elligible to be killed. So for instance, we could have a dialogue option that says "Are you worried those Vampires might strike here next?" By choosing this option it would tell the program that this NPC is allowed to be killed.
It would be something of a chore for those people who want ghost towns to go around hitting this dialogue option with every NPC. But I think it could provide a nice compromise. Plus, you could instantly make sure Nazeem in on the Vampire hit list!
