I don't find it laughable to rank lists either. It's regularly done in WFB (although far less commonly than "hard comp") and typically you'll have several judges who between them play or are intimately familiar with every army and you rate the lists, or a scoring system is devised by which each player can determine their score. While players will inevitably niggle over a point here or there, overall you can get real differentiation between a typical hard tournament list, a more balanced list with less-seen options, an unoptimised list and a total fluffbunny list. You can achieve real variation in competitive players' lists by scoring them. In many regards it's cool, because you effectively get rewarded by taking a poor unit, there's often some unit or model you love but just can't justify in a competitive list normally.
It stands to be noted that players aren't any less competitive in a comp environment, just less extreme lists.