What about Grain Elevator or Red October Factory? The first cap or two on both of those are the hardest caps in the level against the most well-entrenched enemy. After that, it's a breeze for the attackers.
Just about every game of ROFactory I've played has been cut short by the lockdown just as the Soviets were starting to take some ground, or the casualties it took to secure the factory in 5 minutes kneecapped them for the rest of the game.
