One word: Carriers.

The standard assault carrier carries 12 fighters at the most. Tactically a fighter can maneuver and accelerate enough to access nearly any target on the battlefield, and if organized as a group effort they can quickly dispatch a capital ship. However they're easily destroyed and require frequent rearming should they survive. So why not have another 12 fighters on stand-by?

Offensively, 12 assault rocket armed fighters can be launched to contend with capital ships while an additional 12 pod laser armed fighters can be dispatched to take care of enemy fighters without sacraficing the heavy weapons of the first unit. Nothing is worse than wasting a rocket on another fighter that could have been used to take out a destroyer.

The dreadnought carrier offers multiple configurations for accomodating such squadrons.