Office/builtins suggestions

I asked about having builtins in our office/library a while ago - the problem is that there is no wall - just one wall of windows, one wall punctuated by fireplace, the 3rd wall has a door in the middle, and it's open on the 4th side. I pulled up a picture of an office setup with a similar floorplan, what do you think of the builtin bookcases flanking the fireplace. And could I fit a desk w/ computer amid the builtins w/o it looking bad? I don't care for the desk in the middle of the room look, as the wiring would be all over the place. Click through the pictures to #10 & #11. http://www.corcoran.com/property/listing.aspx?Region=NYC&listingid=1876437