actually you bring up good points. as such there are ways of defeating the swarming tactics used in the fleet battle, (but not against an actual swarmer force)
heres some of the specialized ships and weapons useful for dealing with fighter groups.
First of all there are space torpedoes, now in the fleet enagement i did not use them in the anit fighter roll, since i had rushed my fighters forward but these are huge warhead carrying vast destructive potential namely because they poses a huge ring of destruction, up to 20" across (1d20) with my fleet having 4 of them at Mk V and mk VII strength that will usually wipe a fighter group. two are specially designed anti fighter ships, i prefer the gunboat class
whils RoC has his frigate class
but most worri some to large ships, and really shat inspired all this anti fighter work was this vehicle
mainly because you could pack a huge mass of these little buggers even in the ships janitorial closet. if the hodgpodge was partially redesigned(internally) it could hold close to 40 or more of these little buggers. one of the answers to this was the RoC's D-pod
But generally shiops tend to fall into these categories
AF- or antifighter is quite clear what its goal is
Beam/Lance- usually one enormouse gun ie at least almost the length of the ship these will be your heavy long hitters
Assault- heavily armed with a mix of weaponry, mostly centered around a primary heavy turret(s), usually backed up with slightly shorter range weaponry.
Carrier, usually heavy antifighter capabilities, but also either a lance type spine weapon or 1-3 heavy turrets. usually high internal capacity
Juggernaught- several large turrets with as much forward facing firepower as possible, no weapons below class V heavy shield and armor. roughly all veseels will fite into these deignations, because thier weapons tend to dictate thier roles.
1 AF gunboat
1 Lancer Gunboat
1 destroyer assault ship and
1 assault carrier destroyer