I am new to this forum, so forgive me if, in spite of my searches for rejected ideas, my suggestion turns out not to be new.
As leader of my clan, which consists mainly of younger clashers, it has become apparent that a lot of youngsters and new players want promotion as quick as possible. They leave if they don't get it and others abuse it when they do. While it presents little trouble promoting players to elder, the trouble starts when the clan has too many co-leaders. This immediately causes management issues, such as wars being started without the clan having been closed, or while inactive members are still in the war line up; players being promoted, demoted, accepted, rejected, or kicked; and even the clan requirements being edited or deleted by undisciplined co-leaders. While I accept that dealing with unruly members is a management issue, I would love to have an alternative way to reward and thus retain clan members without promotion being the only carrot and demotion or expulsion the only sticks.
I think that a medal system might be an appropriate tool for clan leaders to reward and retain clan members without having to promote them. For starters I would suggest a Distinguished Service Medal for members who display loyalty to the clan by staying with the clan for a determined stretch of time. Such medals could be tiered on a bronze, silver and gold level and would do wonders to curtail clan hopping.
A second medal, perhaps called something like the War Hero Medal, could be linked to the number of war stars won by a player for his clan, again first, second and third class, with a tier similar or even linked to the existing achievements. A third medal could be a discretionary medal to be awarded in circumstances deemed appropriate by the clan leader - not co's - to reward a member for services to the clan beyond what is expected, for instance to the player with the most donations in a specified time, or such like.
The number of medals that a clan leader can award could be limited to ensure that it becomes sought after and serves as a real incentive to remain with a clan and to be active. To serve Supercell's commercial interests one could put a timer with an commensurate gem price to a medal so that a leader can only distribute so many medals in a given time, unless he or she wants to buy them.
So there you have it. Is such a system practical, programmable, or even desirable?
You are talking about kids growing up in a world where you get a trophy for showing up. While I like the idea, and I believe the more mature players would make a game or contest out of it, I do not believe the younger players would think they matter.