So I just had an interesting discovery using your stopGaps script.
I did not want to use Ground Starts because in MP, you have no way of knowing where the airframe is physically located, unless you indicate it's location in the GroupName of the airframe.
So, I initially placed a client airframe on the map and had it set to Takeoff from parking hot. When I ran the mission, as you state in your instructions, the static airframe that got spawned in was oriented due north, instead of being lined up with the tarmac markings and being properly oriented for its parking slot.
I then changed the airframe to Takeoff from ground and properly oriented the airframe. When I restarted the mission, the static that was swapped in was in the proper orientation.
I then went back into the mission editor and changed that airframe back to Takeoff from parking hot. I noticed that the airframe remained in the same orientation that I had set it to when I had set it to Takeoff from ground.
I then started the mission and the statics swapped in with the orientation that I had set the client airframe to when I had set it to Takeoff from ground.
Something else I wonder is.. if you use Takeoff from parking and set the very first waypoint to a point directly in front of the nose of the airframe, using the waypoint to align the airframe in the orientation desired, would that also have the same effect of providing the static a proper orientation?
Update: So, I placed a client airframe in the mission and set it to Takeoff from parking hot. I then created a waypoint directly in front of the nose of the airframe, with the waypoint being placed over the tarmac line, in line with how the airframe should be oriented.... and... when I ran the miz, the static swapped in was in the proper orientation for that parking slot.
I also just tested this on dedicated server and it seems to be working with airframes set to Takeoff from parking.... once you set their orientation when they are set to Takeoff from ground... it looks like that heading is stored, most likely in the Mission file inside the .miz itself.