When ever i used moral in a game I designed (for funzies, never a published game). I always used something like the following.
Morale is a % modifier to all skill abilities. In elemental this would translate to accuracy, dodge. This is not a direct translation. What I mena is that if your morale is at 50 percent, you don't have a 50 percent penalty to accuracy and dodge. You might have a 20% penalty.
Morale Modifiers
Unit lost- subtract the % the units starting combat value was from your total combat value. That same loss applies to morale. So if I lost 20 CV out of 100 I take a 20% morale hit. The other team gains an amount of morale equal to half the amount lost.
General Killed- If the leading hero is defeated, in addition to the CV penalty, 20% morale is lost. a 10% bonus is given to the other team.
Entrentched- If the enemy army was fortified (I think you can do that in elemental, like in CiV), then the defenders gain 10% morale. 20% gain per level of city defense structure if defending a city (20 for wall, 20 for castle etc).
Time- Each round 2% of morale is depleted from both sides representing fatigue.
Obviously spells and certain attacks can modify morale but i'll leave that for another time.
Hope this helps.