Hello, this suggestion was originated in the thread https://forums.elementalgame.com/440710 (Resource Carryover). That's the suggestion:

Currently, when a city produces more than what is needed to finish the current building/unit, the rest is wasted. That produces waste or, if a player wants to avoid it, unwanted micromangement. So the proposal is to change that behaviour, according to city type_

- If the city is a Fortress, the excess production is directly carried over to the new building/unit.

- If the city is a Conclave, the excess is converted in Research.

- If the city is a Town, the excess is converted in Gildar.

Also, if there queue is empty, the next project is automatically selected:

- For a Fortress, the production is converted in XP that are evenly distributed among city defenders and any stationed units.

- For a Conclave, research is automatically selected.

- For a Town, gildar is automatically selected.

So no city will ever be idle, even if the player forgets about that city.