I would really like to be able to select columns to appear in the report viewer, including custom ones I've added to the reports. Sorting by these columns would also be very useful.
It would be very useful to be able to see reports where the user has supplied their email address, so that I can reply to them.
Also, it would be useful to keep track of which reports/email address I've replied to. (ie: keep track of which email addresses I've right-clicked on and clicked 'Send email'). Mark them in some special way.