Yeah I agree about skipping the zombies thing this time around, and by horror I don't mean solely supernatural. Someone mentioned folk lore and that could be quite interesting.
I'm sort of hoping for a more subtle approach to story telling with the increased map size, and supposedly better NPCs. Like you enter a town and hear whispers of something, maybe there are newspapers on the ground for the more observant people to pick up on with more information, you gather clues as you go - the type of stuff you need to keep an irl pen and pad for.
One thing that consistently disappoints me (it was the case in the GTA Online revolver mission) is when you get given clues and intreage, open the map to get your bearings and their is a big fucking circle saying "ITS IN HERE SOMEWHERE, MAYBE YOU SHOULD LOOK HERE". Makes the whole thing pointless, a horror story that you play out yourself, where you are the driving force would be insanely cool.