there should simply be two extra columns.. one that lists the number of deaths, then a simple kill/death ratio.
List is still sorted by frag count but at least everyone could see who the best defended players are.
Something like this (which incidentially is my favorite server to hang out on, heh):
You'll notice that very very few people have higher than 75%, now THOSE are the people to look out for, even if they don't have the highest frag count. ;)