The tag management system is currently in file /tag/manage.php, but linked from the admin block.

Several improvements are possible on this screen :
 - tag type could become just one checkbox "official"
 - the select column could be dropped, along with the select box at the top, both replaced just by a "save changes" button at the bottom. This would also make it possible to perform many operations at once.
 - the "alphabet list" at the top, used to select *users*, is ambiguous on a *tag* management page; this should be dropped, or made to select tags
 - the default sort should be either by tag name
 - the fact that a tag is flagged could be made more obvious than just changing the color of a line
 - there should be a link to "edit this tag" on this page (currently you need to click on a tag, and then on "edit this tag")
 - the form should be converted to formslib

The tag-related settings like usetags and keeptagnamecase (currently under admin->security->site policies) could be moved to this page.