Dominions does not have a 'mundane economic model', because its a WARGAME, not a builders game!
It's about the fighting, with mundane troops, summons, magic spells and dominion.
Not about building the same 'city improvement' a thousand times.
Not about building the biggest city, the biggest empire, even.
It's about the last man (pretender
) standing ...
Btw., I think its much better suited for MP because of that - no endless turns with nothing happening, no 6 hours of play before the first and deciding battle ...