Wouldn't buffing the projectile speed only compound the problem? Not only would you out range the enemy but your shots are now harder too dodge.
Nerfing thrusters might be fix it depends on how hard you nerf them.
It would be nice if we had thrusters that were really good at moving heavy ships but had a slow max speed, so it wouldn't send a light ship flying but it would move a heavy ship just fine. And vice versa with a thruster with a high top speed but it's speed was drastically reduced the heavier the ship was
We would still have ultra lights but, heavier ships wouldn't be completely out classed like they currently are.