I recently got some old PD books for use on my tablet. The books included
some Jules Verne, some H. R. Haggard, and some Wizard of Oz books.
My procedure for getting a book is this:
1) Go to archive.org.
2) Check to see which copies of the book have illustrations. If there are
significant illustrations, download the book from there in .jp2 format and run
it through a script to convert to .jpg. Then put the zip of .jpg files onto my
tablet to read.
3) Only if the above step fails, do I get the book from PG.
If the book is by Jules Verne, there's an additional step: check the list at
http://jv.gilead.org.il/evans/VerneTrans%28biblio%29.html to see which version
is a decent quality translation. It often isn't (and even the relatively good
ones have some problems). (Given an October post here about Dracula, perhaps
I should research versions of the book even when the book was originally in
English.)
This ties in to a number of posts on this list about bad translations, as well
as to posts I made about images, which got lost from the archives (as well as
signups during that time period--I had to sign up to this list again).
Basically, for illustrations, illustrations on PG books are completely
inadequate. What's worse is that the rules strongly suggest that an uploader
use an image size and resolution that may have been sensible 10 years ago but
is ludicrously small for a high resolution modern tablet, and doesn't show all
the detail in the image.
As a start I would suggest fixing the rules, but you'd also need some way to
automatically generate a small-images version from a large images version (for
those people who actually need small images, like over a slow phone connection
at an airport, or who have an older reader with limited capabilities). Big
images can be used to make small images, but you can't go the other way around.
(What is the practical limit on epub image size?)
Previous messages about needing better bibliographical information apply
to images too, especially since images are very often changed in later editions
of the same book.