Library with a Twist

Over the weekend, as I tried to make a clearer image of what the new Library would look like, I made some realizations. First of all, the whole first floor was stairs! That seemed strange to me. And it seemed too symmetrical.
Several factors relating to the stairs and the symmetry drove me towards this design. I believe it opens up the center area and looks more interesting. I like the new structure so much that I don't think we need the "membrane" that we had before.
But it was such a tricky structure to draw that I had to make a model. Perfect medium. I think Jamie might throw this into a 3D applet.
The shaft in the center is like an elevator only without the elevator car.

Open Library

When I designed the Library buildings I was thinking of very open structures that had permeable membranes. In a recent visit with Jane Blumenthal, we found that she has a desire to open up the structures even further than this. She even talked about having the Library in the woods or on a grassy plain. I thought this was so fantastic, because these are spaces that I'm taking inspiration from.
While they are about as open as they can be at this point physically, they still have a lot of visual closure. So, in trying to chop-the-top I ran into a few other design ideas. I think this solution is more elegant than the first, the levels would still be scalloped and alternating, and the top floor is completely open, as requested.

(We're mainly looking at the structure at the top right.)
I'd love to hear feedback.