Super User Role Module
Agaric once had an idea for a module, "Super Role" ...
Drupal super user 1 role module
- runs whenever modules are saved
- gets full list of permissions, and saves it for the submin role
- (permissions are just saved as a text string)
But happily that module has already been made!
Related: The ability to (for most practical purposes) effortlessly clone user #1 is great, but note it doesn't answer the need for a core default administrator role that would allow module maintainers to set sensible default permissions for administration-type actions.