I'm liking the sort of detail you're including within your drawings. You're definitely more of a planner instead of just diving in head first, and then changing the areas multiple times to just see what seems right and what seems to work with each other.
It seems like it's working for you too and that's good. I kind of wish I had the patience to do the same, but I don't think I could at the moment. Perhaps if I was to be really hooked into the contest, but at the moment I'm just at a general level of curiosity.
I'm not sure if it's just place holder textures, and it's a little hard to tell from the quality and the darkness, but I don't think the wooden supports go well with the blue metal textures. I don't think they would be used together either in terms of materials in a semi-realistic structure and setting. Perhaps use a metal trim texture instead? There's a couple to choose from, and maybe replace the blue metal with purple if you agree, since your map is going to take place at a rather dark time? Just a thought.
Also perhaps utilize some corner rails? Although the computer-tech/Spytech versions may look rather awkward when placed outside. So you may have to find alternatives, or even use the existing corner rail models as a reference, then recreate suitable alternates using brushwork, and perhaps use the Propper tool to create them into prop_statics if the need is really there at the end?
I like the fact that you've selected some of the models, like the piping-esque props before you seemed to even enter hammer. Less time being spent switching models around and therefore just staying true to your concept, unless it really calls for a change. Seems like a pretty good method to me.