Congratulations with a slick looking viewer/organiser!
I also have a few feature requests:
* I want to be able to see a "hybrid" view of the library and reader sections: I want to see the library left pane and/or library list view and under that a preview/reader pane of the currently selected eBook in the library list
* I don't like the "borrowed" or "purchased" libraries and want to delete these, but this doesn't seem to be possible. So next request is a more flexible system for organising(adding/deleting/hiding/moving up and down in list) libraries.
So in short: more flexibility of viewing and organising