Thanks for the feedback, I'm aware that they are not the most charming covers yeah.

But as I tried to explain my reasons, there are a variety of book names and when it comes to modularity I couldn't find a right amount of space to spare for title/author.
There is a book called Pip & 1001 Questions and Answers on Orthography and Reading
If I spare only the top half of the page for title then Pip would lost in space, and other one wouldn't even fit there with an easily readable text size.

I've used a plain background, thinking about instead of using a 1000x1600 pixel image for every book, devs could use it as a div(?) with a background color to avoid over-using resources.

In the end I needed to use big texts to help with readibilty in details page..

When I think about all of those, above ones the best versions I came up with.

Hope POs will find what they are looking for.