There is a hook in ACF that lets you add custom field settings acf/render_field_settings https://www.advancedcustomfields.com/resources/adding-custom-settings-fields/. (the example does not work, because the ability to return false will not be available until 5.5, however, you can add other settings.)
I’m not sure if this will help you, but check out this example of adding a default image to an image field. You might be able to accomplish the same thing for a google map field https://acfextras.com/default-image-for-image-field/. The custom zoom level could probably also be added with a little work.
If you still want to submit a feature request I suggest you open a new support ticket. It’s the best way https://support.advancedcustomfields.com/new-ticket/
