I did something like this and it worked very well. I even made a small test-mission where you objective was to get your crew back. I also put the spawn point into a corner so that my team was outside in a different room.
I also saw filbones in one of his missions using a spawnpoint inside turbolift to keep his BOFFs outside.
I've tinkered with the idea of having objectives where you send one team member, via waypoint, to a room and then raise a forcefield between you and them while they do a kill objective that can only be completed behind the wall. It seems prone to being broken, however and should probably be used carefully, particularly when planning for the potential of multiplayer. (My idea there is to have a console in that room that lowers the forcefield but which can only be used by a player, obviously, since the field must be lowered from the inside.)