Additional notification schemes that can be set by user is requested. Even "minimal" is too much for some people, and they would like "minimal minimal". What specifically has been requested is to receive email when the review changes state only. Others may have different ideas when they want to receive emails.
One related item that may help support this is to allow multiple threads of conversation per document location (I can't find an idea for this posted, I think I may have entered that in the older Collaborator request system) - right now, you can only have a single conversation thread per location in code/document, so you tend to be notified when any new comment is logged; for example it would be nice to have the option to only be notified if someone replies to your comments / findings posted in the review, potentially reducing a number of unwanted notifications. Note that some role types (for example, moderator) may still be required to read every conversation for some customers / review types.
Edit: added request to support multiple conversation threads here
