Now that more development teams are using Google Docs to develop project artifacts, it's worth looking at optional add-ons that will build out the functionality that we need.
One that fills a real need is Letter Feed Workflows for Documents and Sheets. LF Workflows quickly automates the process of sending review requests and collecting comments, edits, and approvals of a Google document or spreadsheet.
Workflow lets you run the document through a series of reviewers (the email addresses you supply), each of whom will have a turn to edit the draft and approve the document. As soon as one review completes, the next reviewer gets an email that prompts them to open the document, review and comment, and approve.
The UI is simplicity itself: track the progress of the review just by viewing the document. And if a reviewer doesn't have the Google add-on installed, the review invitation will supply the link they need.