The fight to the death model of every battle as presently implemented would benefit from the ability for forces to attempt to flee. (Even if this is only a manual option, pause fight, hit an "Orders" menu and hit the "Retreat" button).
Once retreat has been activated, the forces should attempt to flee. If they can outrun the enemy fleet or open up the rage to a given value, consider the retreat successful and end the combat.
Lots of room for things like retreating ships having reduced fire rates, or not able to fire or something. Some ships hanging back as a rear guard, etc.
(Of course, all this would be even better if the underlying tactical game code matured a bit. But I digress into wishing for a better tactical model/game...)