Until now, unassigned workers were producing gold, which was great coz it meant during your offline hours, you'll always get some gold through pop growth ... now, you need to assign or it's peanuts !!
but worse, "Free economics" is something that seem anachronistic to a medieval-like simulation. In Europe, Free Economics wouldn't start before economic liberalism in the Netherlands and England in the 17th and 18th ... before that, it would be corporatism (guilds) and monopolistic behaviours that would be commonplace, even while taking into account the financial revolution brought by Italian bankers in the 14th-15th (letters of change, credit, bonds ....)
Finally, with the limitation imposed on banking interests (you don't collect interests if your gold exceed your for storage capacity in your capital), the limitation on transport (maxed at 1M units) and the relative low return on producing gold (there isn't any terrain bonus for producing gold
) .... it's really a problem of gameplay balance.
Have fun,