Here are the book covers now I've modified them after Joe's feedback from the crit. I added a barcode and the address of the publishers, featured on most books, to make them appear more plausible as book covers. I'm happy with these final ammendments and now I need to print them on a few different paper stocks to see which works most effectively. It needs to be a card stock of about 200-350 gsm and it needs to be uncoated so that the covers are protected from scratching and bending. I could add a laminate afterwards if I want it to be extra-protected.