No authority figure needed.
To expand on this, whoever's running the attendance board is basically a glorified maid (Yes, Webby, that's you). The ranking system is generally built by everyone who participates in the subforum, and is in no way meant to imply a player is worse than another. It's just a categorization system to effectively remind us of how we're doing as a collection of people playing this game. We can say "Hm, 20 people have flaked on a game so far this quarter. Maybe the system isn't working," and so on.
The main reason why we're reinstating this system is because before we had it, things kind of sucked. Once we had it, after arguing for a couple of months about the very things you're worried about, things got quite good. Games were active, we needed very few replacements, and no one seemed to be at all unhappy about it.
As far as I can tell, the basic idea is an agreed-upon concept of how much player participation is needed to make this game worth playing. It's a social contract, written by the governed--and the only punishment for non-adherence is loss of the benefits provided by those who act under the rules of that contract.
This is a very Rousseau moment, I guess.
* About activity, not skill.
I'll note here that everything but the S rank has always been about mod-established rule violations/activity, while S rank was more about that +some attitude requirements. That's it.
Incidentally, my next nomination after Zathras is SirBayer. Consider them both my favorite candidates if they continue to improve their games for the next few months.
Finally: I don't know if we caught this, because I'm exhausted, but I'd like to maintain the old rank upgrade for replacing into games. That really, really helped things from just being a penalty system.