Hey Stuart
Forgive Gui, he has this thing about giving general impressions and letting the map author make their own decisions. Good job I'm here, eh?
Firstly the power plant room:
* The walls here need more detail, either some more bsp cuts/additions and/or a whole lot more static meshes.
* I think you should reduce the variety of colours in the lights, especially in the power plant room, because you've got blue, yellow and red, and green just down the hallway in Jawbreaker and it's just too gaudy. You really need to pick a colour and remove it, and my money would be on the red. You have the blue from the power plant, use that to partially illuminate the room with your yellow lights for a pleasant contrast.
* The upper floor in the power plant goes nowhere except that balcony in the turbine hall - why not improve connectivity by connecting that ramp to the highest ramp in the turbine hall?
* I think you should increase the damage-per-second at the base of reactor in the power plant so that it's an instant death.
Lift corridor:
* I really think the jump pads need to be replaced with elevators/ramps - the jump pads are the only ones in the map and really seem out of theme.
* Do something more to advertise the current elevators, try coloured/flashing lights, warning textures or something else to draw the eye.
Jawbreaker:
* Give the green lights a source, and maybe even change the light colour.
Gallery:
* The gallery and access room need more meshes/BSP detail and I felt that the upper floors here should go somewhere to improve the connectivity rather than just leaving a player to have to jump back down again.
* Just thought I'd say that the elevators in here are perfect for lift jumping!
* The round tunnel from galley to turbine hall seems out of place. I'd recommend you at least consider replacing it with an angular corridor.
Turbine Hall:
* The turbine hall in general needs some more meshes/BSP detail on walls because right now there are just too many wide open empty spaces
* The lighting here could do with increased brightness/reduced radius - and here I'm thinking of those spotlights in particular, just to create a more clearly defined spot
* Again here you could drop a colour from the red, yellow and green lighting theme (this time I would suggest green)
* In general you could use more lighting on the ground floor, particularly around the pipes at the pipe entrance end and the flak at the other end
* You need to change the sounds on most of the metal catwalk meshes
(if you don't know how to do this let me know!)
* If you really have to stick with the round pipes on the wall then place grates over them to stop players shield jumping or translocating into them
Now just a few more general comments:
*Like Gui, I really dislike teleports, especially one way and it really does smack of a quick fix for connectivity. I'd strongly recommend you reconsider their use.
*In general you need to improve overall detail in bsp geometry (make corridors and rooms more than just cube brushes, or at least use some vertex editing or brush clipping; if you don't know about these I've always had a soft spot for what is now leveldesigner.com)
* Please learn to use coronas to add that extra something to your lights, but read some tutes on it and don't abuse the power!
* Finally, please use trim!!! Nothing look so bad as textures that just stop, nasty angles, etc. If you don't know what I'm talking about, I can direct you to a great tutorial if you haven't already seen it.
* You really could do with a greater variety of textures on your walls and floors. Plain grey concrete grows old real fast.
Hope this helps and please, if you're doing terrain for your next map, give it a definite identity and sense of purpose!