Membership Plugin - Restriction groups and forums

Hi,

I want to use membership to restrict member to groups (and forums) in two hierarchies only. I want all users to be able to add a new group, and contribute, but then only be able to see groups added by members of a similar level.

My main subscription levels are staff and customers - I can restrict my content as needed but require separation of user groups like this.

Any advice greatly welcomed!

Thanks
D