I've considered pirates for a long time but giving them an economic rationale that fits within the game is tricky. It would be difficult for them to establish a base and create all the support needed (fuel, minerals, etc.) and it would relatively easy to find and destroy them due to jump point choke points.
So, i was thinking about this. The thing about piracy is that the pirate organization doesnt function like a goverment, but they function more like a business. So their economics are things that have clarity of intent. Meaning that most pirates are smugglers, and those smugglers are then aided by police officers, goverment officials and polititians. This have been the norm since the dawn of time and for as long as we have organized crime.
To have pirates in the game, they would have to be able to hijack part of the civillian production. So, if a colony produces infraestructure, then depending on corruption lv, part of that would be diverted to pirate activity. And some of the civillian trading ships are actually smugglers. The way to deal with that would be trough reducing corruption, however, that would explain how the pirates would be able to sustain an economy strong enough to make small outposts. Now, its one thing to have a small outpost, another is to spawn attack fleets.
In that sense, they would then have to spawn fake civillian ships, and then switch them to pirates in the last minute or so. Better sensors would stop raids and etc, however then we have active means to solve that. That would be intercept them during a raid. After they go dark, they go dark. And depending on the results of the raids, have a bigger economy or what not.
With that, it would mean ships with actual military troops and etc, so if the player fails to deal with piracy, he will have an epidemic. Make them board ships will make their fleets rather easy to deal with in early stages and a nightmare on later ones, since they would be able to hijack ships and etc.
I belive thats the best way to approach pirate economy. Now, if thats viable to put into the game mechanics, i dont know, but it would be interesting to make the players pay attention in the civilian production and etc. Like, a colony with recreational drugs would be great for pirate activity in form of smugglers and a good place to be raided.
That would make it players to actually have garrisons, patrol ships, etc. If we have a decent patrol button, or a way to program patrol routes and etc, that would increase the imersion of pirate activity. Give control to the players of how nightmarish they would want pirates to be would be nice too.
Now i understand that i may appear more complex than it really is, so some points into that:
The pirates would not as much syphon the player's resources, as it would just convert all the production into wealth, and then use this wealth to produce the infraestructure it needs to spawn outposts, bases and eventually ships. And that would work in a percentage because if we look into it, a pirate haven with 2 million population is huge. As far as colonies goes, thats nothing. So EM and Heat emissions would be really low, keeping a low profile and being able to spawn bases even into comets or asteroids. Plus, the wealth needed to provide some operations is actually low. It would have to be higher to spawn ships, fleets and troops later on, but that can be achieved by raiding, looting, and smuggling.
The wealth convertion can be as simple as a variation of wealth, corruption percentage, time and overall system or empire development. The amount of infraestructure needed to make 2-3 million pirates alive is low enough that it is doable by smuggling. The pirates could also be able to capture and rearm player's ships, wich in this case it would just copy the blueprint with the ammo, parasites and etc copied and replenished as needed. The amount of missile stocks and etc would be equivalent of a certain amount of percentage of wealth, and the same goes for shipyards, wich would be slower and smaller than player's shipyards, so pirates ships would be smaller as long as it doesnt capture enough of player's ships, wich in this case could even be commercial too. That would just add to the parts they could put together to make bigger ships.
Now, most of that are just a couple of codes running in the background. The end result would be pirates appearing and disappearing and the player needing to find the bases, outposts and etc. The majority of those calculations are to specify how pirate economy's work and to prevent it to go rampart of unbalanced. While i dont know if it will be needed a big overhaul in the game codes, i belive it should be doable, the question is if its worth doing it because of the amount of work necessary and Steve being just one guy working on the game.
But anyway, i tought i should leave my toughts on the matter and i tried to make this as short as possible.