I've made a few attempts at a pirate playthrough with disastrous consequences each time. I can't seem to make enough money to keep my fleet afloat without resorting to more above-board methods of revenue generation. Most of which involve completing bounties that lower my standing with the pirates I'm trying to join.
To that end I posit the following:
1) Allow pirate bosses to accept AI cores for high relationship but low pay.
2) Allow for a low-paying pirate commission option
3) When you've accepted any commission, weight the appearance of missions and bounties to favor your commissioned group
a) I often find that I'll be commissioned with Tri-Tachyon and have a mission log filled with bounties and missions for other factions, and only 1 or 2 for the faction I actually care about
4) As a pirate, some of the missions should be to launch raids against other planets, though I assume if you were to get to a friendly status with them it would be possible to do this by joining the pirate activity in a system, it would still be a good option for a mission.
As a side note, I've logged an obscene amount of time on Star Sector and I absolutely love it. I'm looking for an excuse to play it more, and I'd love to see being a pirate be a more viable option. I know there are mods that might allow for this but I feel like it's an aspect of the vanilla game that would benefit a great deal from some further fleshing out.