I`ve tried several strategic space games and Pirates always do the same thing when attacking other ships, planets or factions... Kill everything.
What`s the point of piracy, people?
It`s to get RICH, not die and fighting means they might die. Pirates want to do things the easiest way for the cash/prizes. You approach your victim and hope he will give you his stuff first then you leave, depending on what kind of pirate they are and how strong.
So here`s how it should go..
1. Pirate approaches ship or planet.
2. First demands any cash or good stuff or "Die!"
3. If the Player refuses- It attacks.
4. If the Player trades cash or whatever stuff he has (even including his own ships as barter with civilians being returned to home planet) for lives and the Pirate goes away.
5. Pirate might still attack depending on personality or strength and a random modifier (attacking because they can with next to no loss). . However most smart pirates should just leave if they get what they want, because attacking even when getting their way means that everyone would just fight in the end.
6. Pirate gets greedier if you keep appeasing them.
7. Possibility to pay pirates extra to leave you alone AND attack a rival faction?
Just how I think pirates should work. Tired of seeing them jus attack everything. There`s one exception to these space games pirates- Elite/Dangerous (though not a strategy game) actually has the Pirate negotiate with you first before deciding whether to attack or not which is really nice.