Private Reports and Subscriptions prior to the users removal can be copied by providing the report link to an existing user, and having them resave the report, and set the subscription back up.
Policies can be copied by another active user prior to deleting the user that owns those policies, this will ensure that the policies are retained.
CloudHealth Support can also migrate this content on your behalf. Please follow the steps here: How do we transfer CH content (saved reports, policies, CH Academy progress etc.) between users?
User defined Dashboards will be deleted as well. You can request from CloudHealth Support to set those dashboards as public.