I do like this shot, but I personally wonder if it would have been more powerful without the young girl. Possibly an older person descending the stairs if you felt like it needed more subject - but I don't think it does. The saturation and colors are great, the evenness and crop make it powerful. The girl is out of place in my mind. I even wonder if you could have cropped it even tighter, keeping the center-line and the bottom crop location - really emphasizing the stairs and the geometry. The area above the second story windows isn't doing anything for the image. I could be wrong, but I'd still like to see it.
Cheers.
Top two. For much the same reason as my other top pick - that unexpected, human interest detail. It's appropriate that this place is called The Powerhouse - it looks like the girl has had the power to levitate bestowed upon her.