I used overnight trains many times in my life. They are great, but if the revival is to succeed, we need better solutions for security. Theft was always a problem in sleeper trains. There needs to be a way to lock yourself in and have an alarm sound whenever someone opens the door with an override.
The European night trains I've been in all have physical locks that are only openable from the inside. Things could be stolen by other people in your compartment, but that's a lot less likely. I also have a preference for the upper bunks/beds, because you can stow your luggage in a nook above the wagon's side corridor, and thieves will have to actually get past you to get at your stuff (except for maybe the person on the bunk opposite you if you're in a couchette compartment). Seating compartments are to be avoided; I can't sleep in them anyway.
> all have physical locks that are only openable from the inside
Really? I thought all these locks can be opened from the outside by railway personnel using a "special key", which of course means that the thieves have access to that "special key" as well.
On DB's CityNightLine, you could lock the door. Of course, the five other people in the room could steal from you. I always just put my backpack against the wall. Would be impressive to have one of your five roommates open your backpack in darkness while reaching over you...
