I've found dead astroneers on my world too. I'm pretty sure that this was just a loot system, as you can find them deep in caves. I know that the new update replaced the fallen astroneers with broken backpacks.
I really enjoy playing this game, but unfortunately, I don't know how to make a habitat like the one you start out with... I pretty sure you need the dropship but I don't know if there is a certain procedure you have to follow in order to set a base up because if I deploy the dropship it will plant itself but stay the same. Any help will be appreciated.