Hey @samuelkrempasky! I think it’s probably too late to completely change the paradigm, but I have some answers to your points above.
For #1, this already exists in the form of List view. This is available whether you’re in the site editor view, or in the page editor view.
For #2, do you mean for the featured image block? That should already be there, and there’s an open Github issue for adding border controls to more blocks.
#3, image sizes are pulled from the WP thumbnail system, which are in pixels. To set a percentage size, you can put an image in a full-width container such as Group or Row, and set a percentage padding.
To add here, there’s a lot of great documentation for most aspects of the editor, and if you’re stuck somewhere, there are forum volunteers answering questions here every day. Please feel free to post your questions.