Also, your tunnel with the teal lighting is really bland ...
How is this?

... the fog render distance was unnaturally small ...
It was even shorter earlier, but it's a small map and I think it might work great.
... there's a light entity without an actual light prop in your fourth image, right above the stairs.
Not sure exactly which light you mean, but the props are occluded by the crazy light glow:

What's the name of the map? I'd love to play it on release.
Out of lack of imagination I call it ttt_town