I created a script that can make a spacer icon (an image that's just a cropped version of your wallpaper at the relevant location) to put on your home screen. It runs a Bottle server and opens a page in Safari where you can tap a position to use as the icon. Then you can tap the Share button and add the page to your home screen. It uses the zero-width joiner (&zwj) as an invisible space that Safari accepts as a bookmark name.
Here it is on Github: 0942v8653/pythonista-homescreen-spacer
Of course you can also make an icon to add a new spacer icon with my pythonista-homescreen-icon script.