Hello,
10. The task to add the image size for the WPBakery products element and also for the grid builder element is in the tasks list https://www.8theme.com/roadmap/ – Product Shortcode enhancement. We are working to include this option in the next update.
13. Unfortunately, it’s related not just to the theme but to the WPBakery plugin and we can’t make the styles of the WPBakery elements work with the object cache.
Regards