Was there any particular reason why, in the Corean Chronicles, the map provided in the book was so dark that it was difficult, if not impossible, to read?

While the hardcover versions of the books had a good color map provided in the end-papers inside the front and rear covers, the interior maps in the mass-market paperbacks were merely black and white copies of the color map. I understand the decision was made in order to reduce production costs, because paying for drafting another map would have been costly. Like my readers, I was disappointed in this, but authors don’t often get to override publishers, especially when they write large books, as I do, which cost more to produce.