One factor that seems to apply to many exit games is that the team playing them are in the room, alone except for contact with the outside world that may be supplying hints, whether by walkie-talkie, over a loudspeaker, onto a screen or by some other approach.
This solitude needn’t absolutely be the case; in the US, the Trapped In A Room With A Zombie series of games features a
real live acted undead zombie in each room, chained to the wall. Every five minutes, the zombie’s chain is extended another foot so that they might have extra shambling radius. If the zombie touches you, you are… not eliminated from the game outright (that wouldn’t be fun, considering you’ve paid for the ticket) but have to sit down, rooted to the spot, and can only communicate verbally with the rest of your team.
This site is not aware of any UK exit game sites currently looking to increase their regular “fully manned” staffing levels. However, an exit game could be distinctive if it were to feature actors or other characters to interact with as part of playing the room. Yes, the cost of labour is expensive. (TIARWAZ, referred to above, has teams of 12 playing at any one time.) It might be possible for a single site with multiple games to contrive some sort of solution, though, with actors who are present at certain points of the game but not others.
One approach could be for these intermittent actors not to physically appear in the same space as the teams, though still to be available at certain points for crucial interaction. Could a game master from another game also act as a character when they happen not to be running a game or performing setup between games? Could it be possible to contrive a reason for a game master to be out of contact temporarily, while they are acting as a character in another game?
Another approach could be for one actor to play a variety of different roles (or play several simultaneous versions of the same character), dipping in and out of several games as appropriate. The entrances and exits would have to be very carefully handled in order not to disrupt the “exit the room” metaphor – there would have to be very convincing reason why an actor could get in or out of the room but the team could not use the same route in order to do so.
A real mind game would be to play fast and loose with the concept of a single permanent benign game master per group. For instance, you might interact with your game master for 80% of the hour in one way – then the game master might physically intrude into the game and interact with you in a different fashion for the rest of the game. Perhaps a game master from another game might continue to act as master for the last few minutes of your game, while you interact with this compromised game master as part of the game.
So many things that could be done, and this is surely only scratching the surface. Wouldn’t be cheap, but surely would be distinctive and memorable!