I've honestly no idea what to vote for. While I definitely want the game to be 'realistic' in regard that I don't want to meet arbitrarily immortal characters, I don't want poor AI to wade into an AoE and die, and neither do I want to escape without consequences after committing a genocide. I definitely would like to see at least one instance where I can see past a side-quest giver (or any other NPC for that matter) trying to screw me over. I loathe encounters with NPCs that 'lure' me into a painfully obvious trap, and then gloat and boast about how clever they are.
I would like to be able to kill anyone, but that shouldn't be a simple mortality flag, script-wise, to prevent them from dying mid-combat from someone else. Watching my party's survivability will be challenging enough, I imagine. In this case, a 'knocked out' condition would be best, I think. If it's an actual escort affair, like "protect this guy while he closes the portal", and he dies either from me, one of my companions or an enemy, it could prolong the quest by having you seek an alternative way to close the portal, but that's probably asking too much and is off-topic.
Another problem is that my immersion is shattered if I attack innocents in a town, fight guards, defeat guards, and then the state of the town's hostility towards me is reset. There are very few workarounds this issue. To that end, maybe introduce initially locked paths through the big cities, and they unlock once you are in bad standing with a city? Kind of like nosferatu having to traverse sewers in VTMB. Maybe Big City #2 could be a Vailian city, or an otherwise darkly themed city that has loose laws and murder isn't frowned down upon as much.
Long story short, the more mortal people, the better, but also the more mortal people, the more developmental problems.