First I most say, I am in love with this game! Sandbox mode is amazing and so is the non sandbox mode.
But something that makes me a little sad is how empty big towns can be, sure I can place down guards and such, but I was thinking. The way you place down monsters, couldnt you do that with friendly npcs aswell? Just npcs running around, no quest givers, trainers or guards. Just random people in your town.