I dont think that you are correct in saying that.
After you finish the chapter you can pretty much do whatever you want.
Even without cheating it isnt difficult to raise a tough army. I like nord templars and rhoduk crossbows. then its just a matter of tactics. pluss with all the heros you can recruit it isnt difficult to have an army in the 100+ range (figure all heros around 10-15 leadership, + fame)(also the powers, that AOE flame thing is badass) at that level most will run from you anyway. then its a matter of taking out the bad guys who took over the nords area... insane amounts of troops at each castle city. I like the hit and run method... siege town, build tower/ladder, defenders sally out to me, i kill them, i leave.... 200-300 enemy kills, train troops get food come back
you can either take out the darkness and be ur own ruler or be vassel to someone, likely you are on good terms with atleast the veiger king because of the tournament.