So I got to looking at the the sandbox set up and noticed there was only urban and uniform. I promote other zombie spawning methods. Such as but not limited to "migration" where zombies spawn then migrate or migrate from edges of map. Or both. Or maybe an option where zombies spawn in particular locations. Basically just more spawner options. I would be excited to see that for sandbox games. Although, the migration spawn system might not work until NPC's are in for obvious reasons. Unless of course there's already a system where the game takes stocked up zombies and puts them in a location that lacks zombie activity.