Currently project admins either have full rights to all activated services or no access at all. Project admins are also the only ones who can add new members to a project.
Often, project managers/leads are specific to a certain discipline. They only need to see one disciplines elements and it would cause less confusion if they only saw what they needed. However, if they are project admins, they will see everything and there is no way to limit it. Permissions to documents and design collaboration teams are inherited as full access. It would be most useful if there was an extra option that allowed certain people to invite and add project members but did not give them full permissions to everything.
I noticed this may be similar to the following ideas:
https://forums.autodesk.com/t5/bim-360-ideas/limit-project-admin-access/idi-p/8528132
https://forums.autodesk.com/t5/bim-360-ideas/project-admin-restrictions/idi-p/8457186
https://forums.autodesk.com/t5/bim-360-ideas/ability-to-change-user-access-back-and-forth-for-projec...
Overall it may just need to be another look at permissions and overrides. Maybe an admin-lite setting or an option to toggle between admin, member, or no access between the different services.