Healing troops

I think there should be 2 choices when healing your troops that have died, 1st choice is already implemented the cost resources for instant revive. The 2nd should be no cost of resources but it takes time to revive them mins to hours to days to weeks.

Reason i bring this up is cause i still have troops who have died over a month ago and refuse to spend the silk, oil, salt and bamboo to revive them.