I’d have to agree that basements are the way forwards, amplified circuits give off enough light to read and craft, are relatively simple to craft and allow a starting character some respite from the world above courtesy of the reality bubble. Doesn’t stop NPC’s spawning in and stealing your stuff. Put your things in crates.
As for Zombears, trap all entrances, windows both outside and inside, they’ll be injured and slow and easily dispatched even for a weak character.