[Suggestion] Door key, Personal Safe, Password guarded door

Hello. Im not a native English speaker, so please forgive my poor vocabulary and incorrect grammar.
I suggest 3 new items (Door key, Personal Safe, and Password guarded door) to the devs for better game experience.
Maybe some of them have been already discussed, though I couldnt check all past posts because doing so takes me a lot of time. (Really a lot)
Im so sorry about that.
So if you are fed up with this idea, please just ignore it.

-about a door key
As you know doors can be opened only by the person who placed it, but that makes your fortress unnecessarily big and inconvenient when you play with friends.
You should place unnecessary doors or must keep login in order to enable your friends to enter / exit your fortress.
So if there were craftable door keys and who have them could open the crafter’s door, this game would better I think.
And keys suit to small stashes.
Dont you think its cool to hide keys of your home under the rocks near of home ?
And I guess its not so difficult for devs to add it to the game.

-about a password guarded door
This is an option of upper idea.
Even for a person who can create a modern weapon such as M4 on just a table (made of only some wood and stones !),
it may be difficult to craft a condenser or some electrical chips.
So I think dial lock system is suit to the world of rust.

-about a personal safe
C4 is often said op, though the main reason of that is you can steal everything in someone’s home by destroying just 1 or 2 walls, or doors.
Of course you can prevent it by making your home bigger, place a lot of metal doors, and a pillar outside of your home to prevent bandits from placing stairs.
But do you really do like that in real world ?
Just place a SAFEs that require password to open or 2 c4 to force opening them !
This can make everybody’s fortress small and save fps (large buildings cost pc power and make your fps lower as you know) and landscape, and server save data smaller !
Content of the safe should be as same as that of chests (not large one), and cost to craft it should be 200 metal fragments (same as that of metal door).

Thanks for reading this !