I think it's time to head into some kind of concept stage where you mess around with colors and lighting to get a mood feel for it. I like the overall composition, it's very nice. It could be a really kick-ass scene. Take the first screenshot and try some stuff in photoshop.
For the walls you need AirConditioning/Cooling, fans etc etc, maybe even have cables running around the walls and roof. It's a server room after all.
Hmm, just googled for 2 seconds on sci-fi server room and I found the concept you're working from
Maybe try and work with what you got there? It's a very nice concept! And remember good lighting will always help hide the "modular"-feel of an environment.