I like the architecture and the theme has promise, just.. don't let it become to cliche fps style.
Just did a single player run-though, here's the synopsis:
A lot of scaling is off. Keep this in mind:
Stairs: 8 units(u) tall, 12u wide, if there are gaps between them, then it is 4u tall, and 12u wide, with a 4u gap between stairs.
Ceiling heights range from 128 (doorway, low tunnel) to 136, 176 (avg) and 365 (main base room for 2fort is an example)
Wall width is either 8 or 16 units, depending on if its a thin shack (8) or a concrete/brick building (16)
The subway room was cool, but the sneaky exits by the tracks had a chunk missing before the doorway, like the wall had not been brought in far enough. The sneaky route up was filled irregularly with stairs that were sort of confusing.
The main tunnel to the subway is great, but the chicken wire doesn't fit (try the fence wire or a nice painted cinderblock texture)
The building that the overhead tunnel leads to (at the spawns) has only one exit, and the floor height looks to be really high, as with another building that is above the 'sneaky' route, that also has a MASSIVE staircase. Lighting could definately be improved in the Subway, and a third route would not hurt, as it would be easy to get an engie lockdown and prevent a further capture.
Some other textures on the blu side were going super reflective and milky-white btw, so try and fix that too.
Finally the entrances to buildings are awkward.. Try and save yourself some extra unneeded map height and keep it even with the floor.
Good map, but it needs some work.