The way I have it setup is, by default users have only "view" permissions to the XWiki space; and all new XWiki tools are written into their own space so that they're protected at space level.
Admin tools (my automated group assignment for example) I have a specific space for and have that space protected completely so that users can't even see the space.
 
I wouldn't worry too much about allowing people to see users and groups lists though.  Restricting all but view permissions is sufficient for most purposes.

From: users-bounces@xwiki.org [mailto:users-bounces@xwiki.org] On Behalf Of Marie Sauvage [EBM WebSourcing]
Sent: 02 November 2007 10:03
To: XWiki Users
Subject: [xwiki-users] Access rights on XWiki space

Hi !

I'm trying to configure access rights on a XWiki to a group of users.
My problem is that I don't want them to access to the administration, I will be the only administrator. But when I deny access on the space XWiki, the users of the group don't access any more to the user's pages, even their own profile page, as those pages are in this space.
Is there a way to give them access without having to deal access page per page and modify the XWiki>Users page to make appear only allowed section with many "if ($xwiki.hasAdminRights())" ?

thanks in advance !
Marie.