Option for defenses to aim at weaker targets first
Users should be able to use gems (about 200 or more) before a war starts to have their defenses aim at the lowest hit point targets first. Hard core players would love this feature to add strategy to their defense. It won't be cheap so it won't be used by most players. Also an icon could appear next to their town hall icon on the war map so that attackers would know beforehand that this player has used the option. It would make hard core clash members happy and would add revenue to the business.
Not everyone would use it
That's why it would be so expensive to use. Plus the attacker would know beforehand that the defender is using it so the attacker could choose not to attack them if they use golems.