Her is some stuff that came out of my head...
The bit of stair in the corner isn't defined. The shape is ambiguous, the materiality isn't described, it is simply an ambiguous bit of distracting stair. Secondly, the compromise you make to include that bit of tread is to give over nearly a quarter on the composition to the underside of the stair which I find meaningless to the imge and actually stops me visually from being able to move forward into the space.
I would have tried to back up if I really liked the stair, but then I probably would have found , as I suspect you did, that the stair encroaches into the scene too much... so then I actually would have moved forward, used a much smaller portion of the stair's underside in the shot which would have allowed us to see more of the second floor to the left... allowing the lobby itself to feel more grand and have a greater presence... AND it would have shown us more of that cool wood ceiling element that is barely poking in. I like that bit of wood plinth you retained under the stair so I would have tried to retain some of that... Lastly I would have moved that whole seating group right to center under the strong vertical you created above the flower shadow. That vertical element drives the eye straight into the stone wall and that would have been a nice zone to have the furniture activated....yada yada yada... my Too Sense.
Nice shot, nonethless, yo.