I think that one solution to see more players in the ranks could be to delete all these accounts which are the last months no active. Every player must have at least few games played every month (5 or 10) if he wants to be ranked.
I think this is a good idea, only some of us go with hollidays for several weeks. Change every month to 3 of 4 months. And instead of losing all your ELO-points at once, it is a better idea to loose points after a year. I mean, take tennis for example. Players loose points after a year, so they must play (and win ) to defend their points and keep their position in the ranking.
If you do it this way, you need less points to reach the bronze ranking. The interval (is this good English??) between ranks has to be changed then, so players can reach faster the silver, gold and platinumleague.
Thinking about it, I think it is just a brilliant idea. Thanks Karaiskakis!