I do not remember what exact sort of traits there are in total war.
Could a great person be a generic name for almost any kind of great people, and what you do with it be defined by some random attributes?
example: a great person is born. It gains a great attacker, great general, diplomat and drunkard abilities. So you could choose how to use it, although it would totally change the use and concept of great people in the game.
And maybe there could be say 3 positive and 1 negative trait.
some examples:
great attacker: +10% attack units stacked
great defender: +10% defense units stacked
poliorcete: +15% attack on cities
city defender: +15% defense of city
favored by the gods: +20% withdrawal chance for unit attached to.
inspiring: +1 movement for attached unit.
cruel: some enemy units have a little chance to flee the fight when they are attacked.
diplomat: can create an embassy in other people city.
Negociant: can improve trade in a city
Great sailor: +1 movement to a boat attached to.
Orator: can improve a governor loyalty, or give bonus to "we love the president day"
Wise: can improve research or cultural output of a city.
Explorer: +1 sight for units attached to
Sick: has a chance to die every turn
Drunk: has a chance to die every turn, or to gain the addict trait
Addict: cost 2 golds to be kept alive
all examples, or ideas.....
Could a Hero emerge from a fight?