im basing this solely off the screenshots, since I have to leave for work soon. (will tweek this post after i play test a little and find something to be incorrect)
I love the lighting. I'm big on contrasting lights and darks. The one difficulty is making it so that there are no dark spots people can hide in unless you purposesly want that spot to be that way. The one image you have with a balcony area looking at a doorway with some dark area in the corner may be one of those spots. But then again, its out of the way and nobody has much reason to go there.
The white brick floor does stand out to me as being off. In other sections that was a wall texture. Even as a wall texture it does feel a little out of place as the other open sections are either team colored or the redish brick and the other whitish wall textures you used are the plaster tf2 walls.
I dont mind the use of hl2 textures, but many will. It looks like you pulled off merging the two types pretty well to form a theme for the map. (will have to actually play it to be sure)
The chair in the intel room may get in the way, if thats not intended, you could lay it on its side and partially tuck it under the desk like it was pushed out of the way. It definatly needs the chair, but maybe not where it would be classically.