I saw the requirement for 7" 10" screenshots, but I'm not sure how these are determined by Play Store. For my app they all look identical to the phone screen shots. It's an App for the visually impaired. No point adding more detail to the screen. Larger is best for this type of user.
Erojam, I had a quick look at the link you provided. I still am not sure if compatibility is soley programmatic, like manifest declarations, or if tablet compatibility is subject to a human review by Android personnel?