The swinging staging area - that's a neat idea but I have some thoughts of caution (all of which you have probably already thought of)...
- As I noticed that your room door swings in, you might want to rig up an "in use" red light (or a simple knock first sign)on the outside of the room to let other occupants of the house know when the doorway will be obstructed with the staging swingers so as to prevent locos and cars from accidentally being bumped from the staging. I saw that it locks in place but sometimes it doesn't take much.
- Will you be staging when the swinger is in the open position? If so, it might be a delicate operation to swing the arms into the closed position with locos and cars on there without having them roll off.
I like that Japanese 7-11. I'm sure somewhere in the U.S. you could find a prototype example!
Do you have bottom access inside the helix? If so, you may want to add a temporary net when not accessing so as to catch the inevitable derailments. If not, a simple chunk of soft foam would accomplish the same purpose.
Thanks for the video. I wish I had the ability to do the same.