I find the economic one to be the most useless branch in the whole game. While changing civics there can be important it is still fairly useless for two reasons
1) The changes are minimal (Mechantalism is useless because giving up foreign trade routes is bad unless you are isolated or no open borders agreements), and things like free market and state property have relativly small changes
2) The advances are late. While other civics flow in through the classical and medieval error the economic advances come much later
By the way i often find that the legal branch is the most important branch because of bearucracy, free speech, nationhood, etc
1) The changes are minimal (Mechantalism is useless because giving up foreign trade routes is bad unless you are isolated or no open borders agreements), and things like free market and state property have relativly small changes
2) The advances are late. While other civics flow in through the classical and medieval error the economic advances come much later
By the way i often find that the legal branch is the most important branch because of bearucracy, free speech, nationhood, etc