Instead of only supporting special entities (nodes, users, terms) pathauto should work for every entity that is accessible via a URL. Users should be able to select any entity type and bundle to specify patterns for them, same for the bulk update. Entity meta information can be retrieved by entity_get_info(). The Entity API provides additional meta information and tokens that could be used in the URL.
Example use case: Profile2 entities.
An alternative is using https://www.drupal.org/project/pathauto_entity