I like in general. i am not sure about increasing subs, you can solve the white flies (it seems some problem with the HDRI, GI, or Antialias filters parameters), increase the amount of reflection in the glass railing and use a reflector map on the camera side (I would'nt add color on glass or walls). Soften the distribution of the rigthside spots (test different types of IES projectors). I would reduce a bit the floor reflection (it seems a bit "wet"). Regards