Looking already way better as the first time I saw this. Might I still recommend some things? I know, I'm really focussing on small things sometimes...
1. The railing could still be a bit thinner. The lower walls look good but the upper walls could use some more detail indeed. Just break the repetitiveness there. The ceiling could use some variation too, now it's just a big flat surface. Some supporting beams, external vents or vent openings, maybe a shaft that leads to a fan, such things could make it more interesting. Just play a little with height variation on it.
2. Looks a bit too repetetive. It could well do it with some valves, some machinery connected to these valves sticking out of the walls, some electricity cables or such. The wall insertion is a nice addition bytheway.
3. The green gue looks a bit too bright for the overall light level. The back of the room is pretty well filled up but the rest looks empty. Maybe spread the details some more across the room. Also, supporting beams sticking out a bit from the walls might break the repetitiveness of that surface. The texture only won't do it. The ceiling could also do with some supports. The lights now are subtle, not overdone. I like them now.
4. That area is still under construction I see. As for now, I'd say the bridge's railing isn't very well integrated with the bridge itself. It also looks strange why the bridge is higher than the two platforms, looks like two unnecessary placed elevators because of a too high bridge.
Heh, I'll check it out and be right back for more...