Hi Flavia and Joel,
I've added the latest feedback from Joel .
for the first design:
1-I tried to make the Title and the Authors name aligned together as much as possible.
2- The back cover I tried to make the text inner space tweaked as much as possible and not to be taken in the side of the mockup.
The second design:
I tried in the second design to make it consistent as much as I can in the back cover.
any feedback will be appreciated,