Yeah, weak morale seems to be an issue in the custom battles. Campaign battles, on the other hand, tend to be much more difficult. You will still have the advantage, but be prepared to suffer heavy casualties if you're evenly matched.
Example: One of my generals, in my Choson VH/VH campaign, who was out solo setting up towers, got ambused by bandits consisting of 1 unit of eagle archers and 1 unit of boar spearmen. I immediately charged the archers and tried to stay away from the spearmen. The archers didn't break until I'd killed all but 20-some of them; and by that time, the spearmen were up my rear.
I still won the battle, but I took casualties of about a third of my bodyguard. In a custom battle I set up after reading the original post; the archers broke after taking 12 casualties and the spearmen after taking 20. I lost 2 of the 48 bodyguards. This isn't really an accurate representation because the strength of the bodyguard in the campaign was 72; but it still shows a huge difference between the campaign battles and the custom battles.
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