I would like to suggest a kinda of clan ranking system. It's very simple and design and it will rank the clans on people's opinions, similar to how teams in college sports are ranked.
Unfortunately it will be just as meaningless as the real life college football polls. In existing polls you have huge biases based on geography and tradition. If you want to see a warlight example of this, look at the rankings of teams in the nations cup. All the polish teams were vastly underranked because, I assume, (1) language barrier, (2) lack of head-to-head experience with the players among the voters. West USA and Poland 2 were close to each other in rank, but West USA got beat by Poland 2 by a sizable margin. Meanwhile, who were the top ranked teams? The ones with the highest profile, most well known players. A.k.a. those with the greatest "tradition." Look at the 1v1 ladder top 10. If it were put to a vote, how many of those players would remain in the poll's top 10? What about Group A of Chokecherry's Promotion/Relegation league?
To the argument that a ranking based on opinion is better than nothing, I would much prefer to establish rankings based on quantitative metrics, and if none exist, hold my judgement until they become available.
I also think that there's already enough clan-related drama on the forums already. This exercise would only fan the flames.
Of course, mine is only one opinion. Feel free to disagree. :)