I like the second photo best (monochromatic works well with it).
Your first photo could really use some HDR I think, as the exterior is really blown out. There is enough detail visible in the background to make me wonder what is out there. Alternatively, could you try same shot at different times of day (dawn/dusk, night), or under different weather conditions (overcast/rainy) to bring down the dynamic range a bit?
Third photo is not bad but like the first is suffering from some blow-outs at the upper windows and where the sun's rays are striking the interior of the building (e.g., centre of the shot). I like the simple colour scheme of black/white and creamy yellow-orange.