I’ve just done a short proof of concept on this and wondered if anyone had done anything similar. What we want is to be able to set an option on the options page, which then governs what custom fields are displayed elsewhere. So, for instance, you may have two different field groups for a custom post type – “complex” and “lite” groups. What we wanted to do is allow users to select which field group to use for the post type on the options page, then use location rules to show the field group according to the option value. All the information I need to do this is on this page:
Is this something anyone is interested in?