I rarely use the Book details pane (Mainly to see a Zoomed Cover).
I like detachable/dockabl panes (like the cover Browser) that I can place on any display or bury under any window.
I like the ability of an Author picture (resizable? in relation to the rest of the window).
The idea of populating on first use

of a author (First use being: the window is made to have focus.)

If there is a significant
chance that Author info is not available, there should be a Unavailable (date) flag, so it does not keep timing out (and a forced 'retry' button).