I have a bit of an idea and couldn't find any mod for this but I think it would deserve a DLC. I am quite sure this would be something special and fantastic.
We have many gamestarts now for X4 that cover well almost every race in the game. There is even a game start that teaches Piracy.
So how about a DLC that introduces a new playable pirate faction. Some of us want to be very very naughty players however it's scope is limited. You are your own faction and play how you want. I don't see a problem with this but consider this. A DLC that Starts you off as a minor Pirate faction. I'll use Yaki for example. In the game you get the choice of
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Destroying them or helping them to become traders.
So you start out as your own pirate faction and everybody hates you (well maybe a little). You have your own battery of Pirate faction specific ships; fighters, corvettes ( I see a use here for a minelaying corvette or frigate) and some support ships like light carriers (fast and agile) and of course something like a battle cruiser. A campaign where you must meet the following conditions.
1 - grow your own pirate faction to a specific size,
2 - Help other pirate factions with the purpose of amalgimating that faction into your faction
3 - While this is all happening you are at war with of course the xenon and have a current war with one of the other factions, lets say the Terrans.
4 - As the game progresses, other factions really start to get teed off with you and start a skirmish war that eventually goes into full blown conflict.
I really think this would open up a very large kettle of worms.
Could even call it --- wait for it --- Rise of the Pirate Factions
What do you Piratey people think