In order of importance:
- Add a reason field for rollback
- Notify the author of the edit that's being rolled back of the rollback and the reason
- Notify the approvers of the edit too (if they exist due to editor's low reputation) of the rollback and the reason
A few times after I've received edit notifications for answer of mine, which other users have (incorrectly!) approved, I have then rolled back the edit, because the edit was in fact wrong. I really wanted to add a message for why the edit was rolled back.
Why isn't there a field to add a (optional) message for why the edit is being rolled back, similar to the "Edit summary" field for an edit?
In addition to the message field, I really wanted the other user to be notified about the roll back, and notify tell the users who approved the edit (if any), so they are more careful in the future.