Don't hide extra settings on global level
Setup a structure to provide global network options

Filters the pre_site_option_{option_name} value to return a global
rather than the network's individual setting. We'll do this for
those that make sense to have a global override.
Configure a default network setting for blog_upload_space of 1GB
Provide a default list of allowed upload filetypes
Allow site admins to add new users by default
Provide a default of no for notifying network admins of new users
Provide a global default for allowing registrations
Remove hacky script used to remove network settings.
Remove items from network info that are managed globally
Provide a default of no for checking max upload space
Remove another globally managed option from network info page