This is a great effort to which I hope to contribute and get others to do so as well. This is far superior to the method used by Manybooks.
On the Harvard Classics, may using the title(s) and author(s) of the works in each volume and rather than the the title and author of Harvard Classics followed by a volume number. If one loads multiple volumes of the HC, he or she ends up with Harvard Classics Vol. __ as the title and Harvard Classics as the author with no real means of knowing what titles are in that volume (other than memory).