I think that this works quite well as the rich, contrasting grains and warm colors of the woods help to highlight the shapes while not making one feel dizzy, as is often the case with spiral staircase shots. The tile on the bottom floor also adds welcome contrast and help to define the depth, shape and perspective. The fact that it is slightly off center balances out the rainling to the right of the image, balancing the over all composition well. If I have any small criticism, it is that the railing at the bottom which is understandably out of focus, bothers my eye. I find the lightness of it distracting. I might have cropped just a bit higher, to where you see the the side of that railing where the wood is a little darker and blends with the rest of the photo. I have tried blocking that out, and I don't see that you lose anything in the overall composition.