Other Workgroups' users who need to have access to the Custom Form field data in our Projects use the System Wide Search on their teams, which allows them to use a bit of a back door to access the Tasks and Documents on our Projects - which is problematic. We are having meetings with those users to define a different procedure for that, but as additional teams/users get into the system it is going to be hard to manage.
It would be great if Admins could customize the accessibility of the System Wide search if needed. Some limiting options like what they are allowed to access and how deep they can go, whether as global settings or per Workgroup.