I dont feel like its a weakness. Tormentor has biggest speed, 2 heaby missile pods, gun point and electronics point and insane ammount of structural integrity. Gauss cannon is just a beast, it has shorter range compared to plasma, but rate of fire compensates that when it gets in range. Also you can build good missiles.
And boost all weapons damage with a targeting module. Speaking for myself I cant see how lack of beam weapon on Tormentor is a problem.