Played this in the IMP yesterday. (You can view the demo by going to the Feedback section of this site and finding your map name)
While I had fun, it's way too small for much interaction or fighting, and a very important general rule that this map breaks is that opposite teams' spawn doors should never be in sight of one another. (But well done for making multiple spawn exits)
Also, since on one half there's a small raised platform and on the other is a water pool, the side with the platform has a tiny advantage. The pool also doesn't serve any purpose (unlike, say, the water tunnel in Well) so it's more of a movement annoyance for people fighting around it.
Finally, there should never be a part where the light falls off to pitch darkness. Use some dim point light entities so that you can see people in the vents.
I like the structure at mid, I think this could be great fun with more areas between spawn and the point to act as a buffer and sightline blocker.