I Have an idea Like:
Humans can find a Safehouse and After find one Create an Protection Around her Like: Barricades, Crates, Stairs and a Lot more, Some houses Have Weapons Like: Bat, Knife and Shotgun, Refrigerators have a certain amount of food within
On Houses at Farm that can Have: Chainsaw and Country Rifle
Killed Bots: When you is Walking around the city, you can see Killed Bots on ground or Into cars, Some Bots have Weapons and You can take those weapons.
Cars: If you Crash your Car so Strong, Player loses HP.
Supermarket's: When All your Food is gone on your House, you need to go to supermarket but Humans Need to make an decision for: Share the site with other humans or Fighting for local
Sleep: Your Character after a Hard day, gonna be Tired, so you need to go to your House and Sleep, if you dont sleep Your screen will shake and vision had become darker, making their actions most hard.
Well, Those is my ideas, i hope like it, so i am Waiting for an Reply