I feel that with the implementation of the Barracks and resources, why not throw in upgrades? I'm sure this is already planned, so why not say what everyone is thinking. As being capable of training troops, why not give the Barracks the ability to purchase upgrades for the Overwatch during a match to increase the effectiveness of his soldiers. Equipping soldiers with an AR2, the AR2's energy ball ability for the Overwatch Elites, giving metropolice the ability to shoot a flare and call in manhacks or something. In doing this, we could also make it so you can level up the Barracks', resulting in reduced troop training, more upgrades to research, maybe unlocking new units(Overwatch elites? Claw Scanners?)
Level 1: Combine Soldiers and Shotgunners, AR2 Upgrade(soldiers can purchase and be equipped with a single AR2)
Level 2: Reduced soldier training time, larger production queue,
Level 3: Overwatch Elite soldier, AR2 Energy Ball Upgrade(Elites can now use the energy ball)
2. An Outpost/Station
Since you are able to train manhacks, metropolice, and scanners, should we not include a building that is focused on just these troops? Same as the Barracks, the core units could be a manhack, metrocop, and scanner. Metropolice start with pistols, and can be upgraded with SMG's and manhacks. Manhacks could be researched and deployed after the "station/outpost" is upgraded and so on. I feel that this would be a good upgrade, and it could very versatile in handling affairs that aren't directly related with a Combine military barracks, which handles Soldier affairs.
I also had an idea for turrets. I have a small sketch here, detailing of how a station could be dedicated to deploying and upgrading turrets in the surrounding "area". A station/outpost could be restricted to deploying turrets NOT in a set position, but in the area around the station. Take this sketch for example:
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The grey represents turrets, the blue is the actual station/outpost, and the red is where a turret CAN NOT be deployed.
You can only deploy inside the white circle, yet you cannot outside of it. Limits the amount of versatility, but it would be overpowered if not, correct?
The icon could be something like:
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