Demeter summons herdables on age up, not unlike the pig relic which does the same in game
Problem statement: The pigs walk to the rally point of the town center/village center on age up, creating a traffic jam of herdables on your resources. Additionally it is a bit underwhelming to get pigs/cows in the heroic age or mythic age that start with 50-75 food. Compare this to Set who spawns 2k food in the mythic age with his animals ready to eat or fight.
Suggestion: Disable rally point on herdable spawn, just make them spawn next to the TC like the pig relic currently does.
Increase starting food from Herdable summoned in heroic or mythic age or add a bonus for Demeter to have herdable fatten faster in later ages.