The roads everything thing is probably a holdover from regular civ land development. It isn't horrible, because it does make it harder for raiders to rip up the warp lines around important planets, and ensures that your defense reaction force, which sorties out of the colony to wipe out intruders, always gets movement back to safety because it never leaves the roads.
But there are usually better uses for construction ships than paving space over.
Pirates are tough against the AI, which doesn't use squadrons or missiles enough as defense. A pirate battleship on its own will die if the player has enough squadrons to stop it, and that is pretty common. If the pirates couldn't turn out battleships without planets of their own, they'd cease to be any threat at all in the later game.
I tried pirate starbases, and unfortunately they inhibited the appearance of new pirate ships. They can handle owning star systems, but not starbases. I don't know why this is, but no new pirate ships appeared once I gave them starbases.
But there are usually better uses for construction ships than paving space over.
Pirates are tough against the AI, which doesn't use squadrons or missiles enough as defense. A pirate battleship on its own will die if the player has enough squadrons to stop it, and that is pretty common. If the pirates couldn't turn out battleships without planets of their own, they'd cease to be any threat at all in the later game.
I tried pirate starbases, and unfortunately they inhibited the appearance of new pirate ships. They can handle owning star systems, but not starbases. I don't know why this is, but no new pirate ships appeared once I gave them starbases.