About #3: I would say that usability without JS should be a requirement. We don't need JS, especially in a low-power device like an e-reader. #5: Why change s

About #3: I would say that usability without JS should be a requirement. We don't need JS, especially in a low-power device like an e-reader. #5: Why change something that is already working well? The extension is .epub, even if it is a zip file.