I also got inquires from our teachers about changing the sorting of files in the list. I think moodle should either support arbitrary order as set by instructors (the way admins set the order of teachers, for example) or allow users to sort them when displaying by clicking headers (as it is done for participants). The latter should allow instructors to set the default sort for the course.
For now, I'd settle for having files sorted by date. We have instructors using same files for different courses as well as revising the files already posted. With some courses having over 30 files in a list, it is hard for students to see which ones are new or revised. Renaming files in moodle is a hassle not only because of extra work but also because they are then out of sync with local copies on teachers' computers.