I have to agree... I love functional buildings! What is the point of awesome looking terrain (like yours) if you can't play? Add a couple of barrels and you are set! HA!
Seriously... somehow I think you should NOT weather this too much. Don't go overboard with rust. The more I look at it, the more it looks like it is working. Sure, you could put some battle damage as it is obvious that it belongs in a battle zone (chemical or electrical stations with SANDBAGS on top tend to be in war zones!)... maybe you could put parts that seem like obvious repairs (like a new side panel covering some breach).
Great work! ANIMO!