Im thinking about buying Rust but its not yet completely what i want. A great survival game could come up out of this game if they take the zombies out and add more and better environments, animals, slower development and not have early guns so people can come together to create a civilization and have groups in steam where they gather around. It would also be cool if they add different structure pieces to place in order make buildings,have more resources, add rivers where people and animals will go to gather water or maybe even the ability to make wells by digging holes in the ground and adding stones around it, preety much make a SID MEIRS CIV V but as a person of the civilization. Would be cool if the game had a slower progress towards gun acquisition so people can go from cavemen with clubs and villages to medieval cities and sieges in castles until they finally reach the modern era where u get guns and vehicles. Early vehicles could be horses that you find in the wild and domesticate. I would also take the zombies and irradiated cities off so this game can be different from day z and minecraft, or maybe even add them later on if something happens in the modern era.
The zombies are placeholders, they are going to be replaced or removed later on in development. When it comes to things like items, weapons, animals and structures - there will be more types of those. The environment will be improved too. These are things I’m 99% sure will happen. I wouldn’t count on any of the other things you mentioned being added, though.