This looks great man. In response to the dirty bricks comment, I've seen plenty of office spaces that look similar to this, so I don't see this being much of an issue.
Alternatively, what I do notice, being an HVAC Design Engineer myself, those red pipes that appear to be fire sprinkler pipes are going right through what appears to be structural beams. This almost never happens as the structural beams are too important. I know this is a "realism" comment that doesn't factor in too much to a "fake" game, but just something I noticed as someone who works in the construction field. It also looks like a handful of pipes just end into a structural beam, which doesn't make a whole lot of sense, I would elbow them into the wall so they appear to be going somewhere else.
Anyways, shit looks good man.