When I restarted my writing journey about five months ago, one of the first things I wanted to address was my book covers. Not that the previous ones were terrible, but I felt they needed a refresh. It seemed the perfect opportunity to also change the size of my paperbacks (something which ties directly into offering hard covers--more on that in the near future). The old size was 5.25"x8". The new size is 6x9. You can see the difference here:
It's not a huge difference in terms of height and width, but the 6x9 feels so much more substantial when you hold it in your hand. Also, because I have more canvas to work with in terms of each page, I was able to go with slightly more space between each line. This makes the reading process easier on the eyes and, in the case of The Nullification Engine, the page count went from 430 to only 453. I kept the same cream paper color and matte finish for the exterior.
Here's a snapshot of the interiors of The Assassin's Blade and Engines of Alchemancy (both 6x9 editions):