Currently, pirates have a bad habit of going extinct when the AI develops Novalith cannons, as they tend to target the pirate base quite frequently and if it gets hit twice the pirates go extinct from losing their planet. As the TEC rebels are based around an alliance with the pirates (pirate reinforcements, pirates act as allies, can push with a combined pirate/player fleet etc) and it is in their best interests to keep the pirates alive, I have a suggestion as to how to make the pirates tougher to take down, without giving them a starbase or planetary shield etc.

Why not let a TEC rebel (that has Truce Amongst Rogues) build a starbase with Auxiliary Government at the pirate planet to stop pirates from being defeated by planetary bombardment via novalith cannon? Obviously it might take some technical rejiggering to get the Auxiliary Government to work on a non-player owned planet, and for all I know it may be impossible, but I figured if it were possible to do, such an option would allow a TEC rebel player to keep the pirates alive to carry out their nefarious plans for a cost, rather than currently where the player is powerless to keep the pirates alive.