Brick column - a better displacement maybe? Specially visible on last render.
Glass - do not want to go full anal about it but... is it a glass at all? If it is, give it a bit of greenish grading. Glass is slightly green in nature. Otherwise I assume it is some sort of plexi. Also stronger refraction will be in place. In some places due the high transparency you can't read it as glass, and it is a bit confusing. Also usually the way glass floor/railing is made, they put together several layers of hardened glass sheets together. On renders of yours it seems to be only one piece. Also give it a few mm chamfer on edges. :)
Floor - bump map is a bit to strong.
I am not questioning design but, adding few wall washers along brick wall on second floor, could possibly make it more interesting? Or piece of art on the wall itself. Not sure if size and choice of art is good, I had a little time on my hand :) . It seems like competing with chandelier. See enclosed picture.
I took a freedom of slight adjustment of curves and exposure.
