Funny thing about book covers. A good or even excellent example may or may not inspire you want to read it. A bad one will actively dissuade you.
The Grauniad ponders the future, complaining that the small thumbnails are 'inscrutable jumbles of pixels that tell us little about the work'. I disagree. Personally, there's skill in creating the right look. After all, postage stamps can be a work of art. Like this, my latest read set in Iceland. If that cover doesn't say Nordic Noir, I'm a pickled herring.
I don't know about anyone else, but I ALWAYS go back and linger on the cover image, despite the fact that the Kindle starts me at chapter one. I go back. I savour. I browse. I dally over dedications, dates and details. It's naughty of the Kindle to beam me in at that point and I would dearly love like to override this particular function.
Furthermore, I won't abandon my endless fiddling about on Adobe Photoshop to achieve the perfect ambience. And yes, I shall endeavour to fanny about with fonts to make them readable in such a small format. I shall even, no doubt, add too much subtle detail which a Kindle might not even see. It makes me feel better, like the old story of the medieval sculptor insisting on carving the unseen rear of the stone pillar.