I have been playing arund with modding unit statistics to try an generate longer lasting standup fights...

One thing I did with add 2 to the morale of every unit in the game, but I am seriously considering removing this change as even a peasant unit with fight until recieving 50% casualties in a simple head on fight of equal numbers... And a remotely professional unit will happliy fight until receiving around 80% casualties...

I can't decide to the "realisim" of those sorts of figures... I mean yu can still route units sooner by ganging up on them and flanking them, etc... But is it reasonable for any old units to fight nearly to the death before running in a simple, equal fight??

For slowing things down I found giving all units a big bonus to all unit's defence stats. I am still experimenting, but as it slows down the rate at which individuals in a unit are killed off, it reduces the rate at which morale penalties (from casualties) are piled on..