Retreat strategy options

Or all of your fleet could have get crushed, if attacked by a far supirior force...
I personally think, that if you let your fleet attack until 50% of it is lost, ´most of the ships that start retreating will be lost, too. Therefore I set my retreat options to something like "enemy fleet is 200% as strong" (don't remember how it is called, but that is what it is). In my opinion there is no best retreat strategy. Sometimes something will work, but you will surely encounter it failing at some other important point...

I don't like retreating. Who knows if I can pull out a pyhrric victory?

I keep it simple, I have retreat set at "never". Heh.

Zteel, I change mine to exactly the way I want it - I edit "Optimal Range" strategy so that it never retreats unless "all weapons are gone" and have everyone with that strat in 1 taskforce of the fleet; all my repair ships/supply ships have a modified version of "Don't get hurt" where retreat options are set to "immediately" but not to leave the sector until defeated and they are in there own task force of the fleet too. Everything else non-combatant not in a fleet is set to a created strategy called GTFO which is basically just a "Don't get hurt" strategy modified so that it leaves the sector immediately too (not that they are likely to get away, lol).

As for your second question, its probably the percent of weapons undamaged + shields/armor/structure compared to your own.

This is a great question that I have wondered about myself. To be honest, I have tried to make this work in the combat simulator, and have been unable to get any sort of consistent behavior. I've tried frigate vs. battleship, for instance, with the frigate set to a strategy of retreating when the enemy is 75% our strength, and the frigate just plows in to the attack. I've tried greater ship counts and a number of other permutations. As far as I can tell, whatever algorithm is in place does not work consistently, at least not in the simulator.

The most consistent settings are those based on the individual ship damage. I'm getting things to retreat and actually emerge from battle in "operational" condition.

The drawback is that they could have contributed another shot or two before being destroyed, but that's the trade-off if you want combat units to get out alive. But repairs are easier to manage when spacecraft can make to back to the yard under their own power, and that means the unit is combat-ready much sooner.

If one is altering strats for the AI, it's important to keep in mind that it doesn't hesitate to make suicidal attacks on the map. So the retreat when enemy strength is too high is obligatory for them, even if it doesn't work very often. Humans don't attack powerful fleets with a single DD, so this isn't a problem for them.