Users who can view a document need to have manage rights on the documents so they can add versions in response to review requests. Currently, this right can be automatically applied by a project template, but this gives too much access. Consequently, users must apply manage access manually to documents every time they request a document approval, and revert to using email, which is easier and more natural for them, but much less efficient.
Please allow the system admin to configure manage access to documents automatically via configuration.
One way this might be accomplished is by by adding an "ADD DOCOUMENT VERSIONS" option to the project access panel:
"When someone is given access to this PROJECT...
Give them access to...
ADD DOCUMENT VERSIONS"