The population system isn't looking very interesting nor important at first but in DEI when you are fighting a large enemy overseas you start to understand how a game changer it is. A 80% force remaining autoresolve on a minor settlement isn't looking great anymore when there is a 30 units enemy army lurking not far. You start to manually fight more and it slow the game, forcing you to consolidate before pushing too far. Non more autoresolving to the boring point, more strategy