That being said, benchmarking the Total War franchise and their take and how the morale works dynamically, would probably be the safest and most effective way to depict morale in battle.
You mean Bannerlord battles should be 30 seconds instead of three minutes?
Ok, jokes aside, why Total War style morale would not work:
- the Total War AI is not the best, but tactically it is still miles ahead of Bannerlord. I mean it can at least approach you in a straight line, send horse archers to the side, try to retreat the skirmishers through the infantry lines in time. (not that it suceeds, but it tries).
- since the Bannerlord tactical AI is incapable of advancing in a straight line, or generally keep some cohesion, all formation based morale effects ("concerned by enemy at flanks" "unit surrounded") would be an easy win for the player. Even without much tactical thinking, the player could spit his troops in two, to always have the morale advantage. The easiest would be to advance with the enemy, and go around the battle with cavalry following you.
There are some effects which are in total war, and could be used in Bannerlord though:
- moral attribute should be maximized per unit type, should not be a general value valid for the whole company
- it should be measureable. Eg. peasants should have 40%, knights should get 80%, berserker types 100%. (or on D&D scale, 6 or 7, 10 and 12)
- food, wins should give a bonus on top. Eg. in a successful, and well fed army, the peasant could have +10, or +20% morale, and could have 50/48 respectively. But should still be worse then a knight without bonuses (80) or even than a knight with a penalty (~70).
- morale check should happen: first death (maybe 20% losses), 50% losses
- extra morale checks: against inspire fear units (berserker types, maybe heavy cavalry too, ogres/nazgúl and the likes in fantasy mods)
- morale bonus: banners, or in certain cultures, champion units should give a bonus
- there should be a check for fearless units (berserker types, honor guard, skeletons, etc.)
+1: chasing enemy routers is the most boring part of the battles. I think there should be an option for surrender, and put down weapons.