ok i just gave it a quick run without opponents.
In general you need to scale the map up by at least 1.5! There are too many areas where you get stuck while jumping around or you're bumping against corners. Give the player more space to move!
Completely rework this area:
it's just too cramped, the ramps are too steep and movement is restricted to going up in normal walking speed, otherwise you get in trouble bumping against everything.
The whole environment seems to be cut at a given height. why? Feel free to add some pillars reaching into the sky and vary the height! This helps to get rid of the boxy feeling.
This just jumped into my eye cause the "hole" in the wall completely brakes the structure of the brick texture. Use the brick-texture as a guideline and cut out the hole along the lines that is given by the bricks, and don't just cut right through them
And i really don't know about all these railings... I'd get rid of at least 80% of them and only keep them in some places where they more or less add as a strategic component to the gameplay. I found myself running into them and hindering my movement far too often. This is frustrating, as one of the most crucial gameplay rules should be that the player feels in control of his movement and should be able to focus on his opponents rather than be forced messing with his controls to manouver through the environment. And the need to be jumping to be able to fire a rocket over a railing onto a lower floor just doesn't work with the fast xonotic gameplay.
So this may have sounded a little harsh here are the points that i found to be very good:
The whole map has a really nice feel to it and i really like the little details that add to the atmosphere like the broken parts, the pipes where you can jump on, and the water.
The layout seems very promising and with some testing this can be a solid stock-map.
So please keep working on it!
And scale it up!