That is correct pretty cool if we can get pirates to raid those. They at least need to be more mobile. Back at launch they would move across the galaxy to harass you but they 'fixed' that as it caused turn timer slow downs. Now they rarely move far from the shipyard.
I definitely would like more active and mobile pirates.
That said, I'd prefer that they don't randomly roam around the map, and generally stay within a certain action radius (say 25 hexes) of their shipyard. Pirates are always a "quick in and out" kind of folks, which means they want to be able to flee back to their home easily.
So, while it would nice if their shipyards moved around (and, hey, why not have those shipyard defenses improve throughout the game), I don't want pirates roaming free through my empire a hundred hexes from any home base.
I'd like to have them recognize where trade routes are, and move their shipyards to within their action radius, though. Same goes for mining colonies.
Last thought: maybe it would be nice for them to raid starbases, too, particularly ones not close to any planet?