>>20911472btw this is what i mean by the window thing
maximum comfy, although i'd use smaller windows and a not so big archway
you can also put the staircase inside the wall like this, removing the need for a staircase that takes up space
furthermore, it would make it fairly easy to hide the stairway behind something like a bookcase that opens like a door, preventing anyone who enters the main floor from going up any higher, or so you could hide the entrance to the basement and use it as a safe room