BuddyPress.org

1) Moderation suite – look into the various filters – bp-activity-filters.php, bp-forums-filters.php

4) Alter main menu of site – look into bp-core/bp-core-adminbar.php

5) User can select password – already exists

6) Multple unique identifiers – would be a cool plugin. are you thinking of custom profile urls?

7) Reserve usernames – in WPMU you can blacklist usernames from registration, not sure if such a feature exists in single WP.