No NSS is not a bad thing, I just hope the Navy doesn't adapt their system to the Air Force's where class ranking is less a matter of your flights and more a matter of how well you shine your shoes.
I would also see us hate to adopt the AF policy of weighting check rides more heavily than the average, daily syllabus flight. It seems to me that system is a huge mistake. Your ability to perform predictably every day seems much more important than your performance on one event.