i always want to have a variety of troops which I can donate at any time to fellow members. But I rarely use many of them on my regular attacks. That means when a fellow clan mate requests, say a healer, I have to start training one, make room, and than wait the time for it to be ready. By the time I have the troop ready someone else usually donates barbs or archers or something else other than what they asked for.
I realize I can use gems, and I often do, but to use them all the time I will run out fast!!

My idea is a stable, or whatever you want to call it, which can prep and hold troops that can only be given away for donations. The troops would just hang out until you choose to give them to members of the clan! And the troops in this stable would not count against the army you are building in preparation for an attack. It would allow my attacking army to be at the ready but also give me the option to have, say one healer, five hogs, a couple wizards and a dragon sitting around for when someone makes a request!!