What if "Pr Thrusters" are Primary Thrusters and give you boosts that are speed 2? And can only be equipped to ships with boost already.
Could be interesting, though hell it could be broken (as a pseudo SLAM but alowing you to fire), but I could see it being useful for Imps and the Awing, and T-70.
That upgrade would be silly on interceptors, because they can also take Autothrusters. Like prenerf phantom silly. In fact, exactly like the prenerf Phantom, except that he has more choices. And there would be similarly powerful combinations on the T70, also. Give PS9 Poe BB8 and Push with the ability to boost at speed 2. Free Barrel Roll, 1 OR 2 Speed Boost, Green maneuver, Focus Action. Already possible other than the longer boost, but giving him SIX choices to boost, including 3 really fast ones, would be silly.
could also be TEch
in fact, probably is because why would you give a mod to an X-wing (integrated)?