You guys are making the mistake of thinking the "barracks" are modelling an actual set of Quonset huts. AH models aircraft, but the rest is a GAME...
and the "barracks" arent really troop boxes. They're icons that STAND FOR the bases ability to mount a capture attempt. Their toughness isnt measured by what happens when you strafe a quonset hut or slit trench, its measured by the way game balance shifts when you tweak it.
Make em too hard, and its too easy to capture so the maps change too fast -- as soon as there's a numbers imbalance the big side is unstoppable. Make em too soft, and the maps last forever because you cant find anywhere with troops.
From a game standpoint, seems about right now.