I realize the pirate system has been discussed repeatedly and this idea has probably already been suggested but i just figured i would blurt out my thought on the subject in the beta feedback given that pirates continue to be a disappointment.
Just a thought, but rather than, or in addition to the pirate bounty system, what if pirates would spawn in varying numbers (obviously not excessive numbers) at random all over the map (similar mechanic to the tec end game culture thing insurrection that spawns rebels all over). Also, it would be interesting if the pirate faction also spread and conquered planets and upgraded over time, and used this empire for the bounty spawned missions against factions instead of spawned fleets.
Pirates wouldn't necessarily target a big military empire and risk their ships and lives over a bribe or bounty unless it was really worth it. instead they would be stalking from the shadows waiting to attack unsuspecting traders and isolated ships for loot and salvage.
This would obviously still be not used in mp games, however it would add to the role-play and realism of empire building for people who role-play and create singleplayer scenarios. remember it is not just always enough to conquer a planet and move on. you need to maintain and protect your colonies from all threats foreign and domestic!
This ofc is all a secondary thing and not necessary, but its just a thought for consideration. sometimes little things can add to the overall experience.