If "pirate" was renamed to "outlaw" and nothing else changes, there would be no difference other than a name change. People would still want to join "Outlaws" because "Evil Is Cool" or they want to play with a handicap (pirates as a faction have junk). Players who want to be pirates and have access to good toys to play with should accept a commission and get benefits on top of preying on their enemies.
It would be nice if independents and pirates were not monolithic. As they are, they both feel like major factions. Do to one, do to all.
As for the player's avatar, he will (probably) be the next up-and-coming major faction, too special to be lumped in with the rest of the faceless Independents or Pirates.
P.S.
Maybe one thing that could help, if pirates are permanently hostile, is pirates should offer missions or otherwise take help regardless of reputation (i.e., lower threshold from hostile to vengeful.) They are so whacked out or insane that they do not care. Pirates as a faction (should) seem like one angry stupid chaotic evil family. They hate your guts (for no logical reason), and will kill on sight, but if you dock with their markets, they will unconditionally let you land and gladly trade or offer missions. Or perhaps block docking if there are aggressive pirate fleets nearby ("Fight us first!") or meddling faction patrols nearby ("We don't want to be seen by the cops near you!")