I don't really know how to explain this, in short have different vanish groups that can see different players. It can be integrated with other parts in the plugin, but I am suggesting this feature for the purpose of admins seeing mods, but mods not being able to see them back.
vanish.group.admin -- assigns vanish group
vanish.group.view.admin -- allows seeing this vanish group
vanish.group.view.* -- allows seeing all groups
^vanish.group.view.admin -- takes away view that specific group
Another feature that would be cool is /vanish (max vanish level), /vanish mod (allows for mods to see you), /vanish admin (allows admins to see you)
It would be nice to either have a few groups(Admin, Mod, VIP) or the ability to make your own groups. Another nice feature would be the ability to tie in other perms in these groups like towny does for mayors/assistant/resident (townyperms.yml).

no comments? :C

I've been a bit busy. This sort of system is planned for 4.0

Can't wait to try it out on my server, mbax. Thanks!

#183