Considering the new type of attackers, and how that can be annoying for some people. I though that would be interesting to add an option to solve this issue.
Security room. Dwellers set to this room will help with any incident, considering that there is space for them in the room. At level 2, they will be able to help with full rooms. At 3, they can use stimpacks by themselves.
To build the room, or improve it, is optional. I don't see any problem with that, unless you are one of those players that have ego issues with someone elses way to enjoy their games, or lack self control and consider this a cheat. =P