that's a good idea. I wanted a defense mechanism in this game because it is really annoying to defend against the shark while you're building or something.
There should be a nighttime in this game because it would make it more fun to play, and seem like a real world, not like Antarctica where it is sunny all day for half the year. Unless you live you live there.
This is a great idea. Maybe add some different obstacles or things that makes it harder to survive, like storms or something. Also along with the spikes, you could add reinforced foundations that required scrap because at the time there isn't enough uses for scrap.