I would imaging that for a lot of instructors, they would probably prefer to have "Grade export display type" set to "Real", but have a option to export their final gradebook to Excel spreadsheet which has an option to include the "Final letter grade". (See my screenshot).

Under the 1.9.x gradebook (Grader report) pull-down menu "Choose an action", instructors could edit/view the range of the letter grades already. It would be nice to also have an option for the "final" letter grade to be exported to the Excel spreadsheet.

Just my $0.02.