a nice feature would be for IP address to be shown to anyone with admin privlidges. Maybe even a config option to assign a seperate security level with this function...

This is a good idea - I would like to see the IPs, but don't want it visible for users. I already hide the number of registered users from non admins. I would also find it useful for the basic admin's show/edit users display to list more than just username - their email address (so I can delete user's who subscribe with broken email addresses) - and their banned status (even if this is just done by colour-coding their username in red). We have started on the policy of banning users who choose offensive usernames - obviously if you just delete them then they can recreate them, so we could do with an easy way of seeing if another admin/moderator has already banned them.