Given that the destruction of Barracks/Forts causes the soldiers to become unemployed (not great…) and there’s no decent way to transfer troops between stations (nor to properly deploy them whilst a barrack is being upgraded) I think that separating soldiers from the regular building-:-empoyee tie into something more akin to the cows-:-barns mechanism might play better.
Basically have a “Military” screen like the “Professions” and “Resources” but one in which you can assign and re-assign troops to/from specific barracks. Unhoused soldiers end up at the Town Centre and can become unruly after a while (or head to the pubs and play drinking games).
I like the idea of a Military screen. Perhaps include a way to decide which soldiers and guards get which weapons and armor. Maybe also a way to hire mercenaries or guards to help protect against bandits.
Honestly I’d be happy with an upgrade so I don’t have to manually tell my soldiers to deploy. Maybe a mechanic where if my walls are breeched they automatically deploy to the area. When my city gets big enough, pausing the game and finding my barracks and then picking a target is tedious.
Maybe also a marker to denote the invaders? Right now I can’t always tell them from my towns people.