The problem with this was that once there was a breach in a lab network, everyone was pretty much dead instantly.
After a while I started thinking about perhaps having fences between all the individual lab rooms as some kind of security measure, but this brought up some pretty complicated AI requirements on the part of the civilians.
I'm still around, and SBTF is still being worked on, but the pace has been (obviously) very slow since the summer.
I would rather do this then the (to me) obvious alternative; just get rid of everything except the rifle.
Hopefully interesting player choice will arise from this, especially in team games.
After this was done I started feeling that the labs constituted too large a safe zone, but after iterating on that a bit I found that I still liked the size, I only needed to figure out at way to make them slightly less overpowered.
I tried having some small percentage of labs generate little dead-ends, which caused the downstream algorithms to generate breaches inside the labs.
On a gameplay level this means that players and civilians can freely pass, no shots are blocked, but Beasts and Creeps cannot pass.