Best Practices for Managing Content?

Trying to understand the best practices for managing content within Articulate Rise in my organization.

We have a large amount of content creators and I am worried about the probable situation of someone forgetting to add a collaborator and going on PTO or if/when they leave the company and it will require Administrator intervention and our Administrators are elsewhere within the large corporation I work at.

Is a Group Admin able to add collaborators to items within their group?

Is there anything on the roadmap for better management of content so that a giant list of emails doesn't have to be manually added for every piece of content?

How is your organization managing content within Articulate Rise?