How about this: Either (A) make it impossible for NPCs to attack each other, or (B) remove their ability to attack unless first attacked by the player. (B) svcks. (A) isn't a bad idea, but hopefully you get what I'm trying to say. Personally, I think a little realism is needed. I think whoever said it earlier had a good idea, that NPCs shouldn't be required for quests, that there should be an alternative to completing it. There should be an alternative, yes. I'd like to see more outcomes for quests, dependent upon how you completed it, and who you completed it with. That would be nice.
Both A & B svck, equally.
There should always be
more alternatives to quest completion, more specifically the
main quest itself. Whether we want them to be essential or not, many NPC's are going to be needed
alive for some quests.
NPC A wants you to take
object x to
NPC B. Of course A & B should be spared acts of random violence by the character, because you'd assume they're necessary - especially for the reward from
NPC A.It seemed like Oblivion tried to fix some of these special NPC deaths by making them
unconscious only. This completely destroyed the experience. Most of the time, common sense should prevail - that voice in your head telling you that
you shouldn't have killed that NPC is most likely right. But for the sake of roleplaying, and hopefully wielding concrete knowledge that you in fact
don't need that NPC anymore, you should be able to declare war on 100% of the named population. These freedoms are important to make the experience feel more open.
Making it
impossible for NPC's to attack each other not only doesn't make any sense, it would ruin the experience.
If the NPC is generally hostile, or just doesn't like you, he/she should be able to attack you unprovoked. What's wrong with that?