Not judging the overall design, which would make me mentally ill if I would stay there for more that 1 hour, and the mix of green grass and red glass, so let's get to technical stuff - things that bother me most:
-noise - render settings or materials optimization would be required, or simply longer render time
-metal/reflective materials - they simply don't look real - they are too uniform, glossy, and plastic-like
-even if most of the materials are purely black&white, I think there should be some little tint of warm/cool hue introduced, maybe even simply by changing color temperature in vfb, such monochromatic look is not realistic