Dyr, i'm not sure that the place in the classment is only linked to the fact that you are a good or a bad player.
Citadels is a game where the luck is a BIG factor.
I know for example that Askalab is a quite good player... but at a time, he was in the 80's in the ranking system... because no luck! So knowing that, (he is good + he has low points), nothing will push me to play with him.
Another point is that there are multiple groups of players on the server, who don't allways mix...
I play often with my friends... So the ranking has eventually a signification between us, but it has no real signification compared to other players, that i play only occasionally with.
So i think that to have a meaning, any ranking should be placed in a tournament system, where all players participate equally and, as luck is a big factor, it would have to contain a huge number of games.
As it is now, i find the ranking system is a "fun" functionality, but not really indicative of anything.