I like this idea. Map progress would determine better team, it could cause problems on map level though. Other than that sounds better than my idea.
I'm not convinced that the addition of tactical zones will actually increase the level of teamplay. It might turn into a reason for a player to stay out of the cap zone. He can get enough points too by staying out of the cap and making his kills from out of a tactical zone.
You might be right.
I just had the game on Fallen Fighters where we were fighting with the Soviets for C and we had something like 2 minutes left. I've seen only a couple of guys willing to risk and get into capzone before time runs out. We had much more people inside the Univermag. I realize the importance of covering fire and sharpshooters, but there is no possiblity that we'd require as much people back there.