Over all, Very nice job,
but there are some problems with lighting, use of space/map fixes, pick-up placement, spawn-facing direction, needs signs, and highlight to some map details.
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Lighting=-
-stage one of map-
point B's back ledge
the silo missile
-stage two of map-
Red's side top spawn, AKA
Gate 2
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Use of Space/Map Fixes=-
-stage one of the map-
Gate 1's fences are setup gates, not a lot of cover, and this path is generally not used.
The second floor of point A needs a hollow-out and a bit of cover.
The Silo room, Near point B, needs a hollow-out behind it (seen to the left in picture, maybe with a small health kit)
The Hall between the Silo and the Hot-Dog stand(?) needs some cover (barrels) and why have a vent-shaft that leads nowhere?
The Blast Window, people can hop on the ledge of it on both sides.
The Area behind the Hot-Dog stand, too open and spacey, either reduce the size or make something there.
-stage two of the map-
Gate 1's Gate, very bulky and is missing texture.
The Area outside of point B near caves, needs some more clutter, things for scouts to jump off of.
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Pick-up Placement=-
-stage one of map-
The Area that is in front of point A needs a small health kit and ammo.
-stage two of map-
The health and ammo in the
broken cylinder, I am sorry, but I abused it to give the engies a hard time with my pyro. So if I can do it, then it needs nerfing.
The secret waterway from point A,

why two small health kits?
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Highlight to Details=-
The Flight Control Tower on stage 1 could be taller and have some flashing lights on it.
The area outside of point B and above on stage two,
The Mining cross-ways could be easier to noticed.
Signs could have been used to block and direct players and some of the spawn directions through me off a bit some times( like stage two, Red spawn facing elevators, not the exit).
So loved the map, keep making more, and fix stage three's gates not opening.