In the style of the person before me...
1. Yea, alpha test, might be inbound, if not would be good to have s hort range radar, nothing fancy to tell you what is coming, only that something is nearby in a particular direction.
2. Once you kill something it's gone, I've personally never had anything come near my base when it's built either. Not even them giant gnats that just wander around and used to use my base as a grazing area, but don't now that I'm here.
3. Water? Maybe, but honeslty what would it even be used for?
4. Yes, there's already an item that gives full health, just need to research each of the healing items (more specifically the mushrooms) and you'll get it.
5. We're engineers, not wizards. It's a factory simulator, not D&D.