I also follow this plugin with great interest.
I would also find doors as a boundary for the individual floors very good. Even more important for the outside than for the inside.
A button to call the elevator could perhaps be attached to these outside doors?
Also, if that's possible, the menu only appears when you click the button (or use "F") and not because you happen to be walking down the hallway.
Is the elevator really a room or just an area that you can design yourself?
Yes on future API update we maybe able to add button on the outside, the elevator will have 4 doors, for the design it's not editable sorry but this was a 10min build, I can spend more time and add more details but ATM this is a place holder for me to get the underlying code done 👍 as I said this is just a proof of concept atm