[Suicide Junkie]

I firmly believe in letting the player's design and strategy determine whether a fighter is a dogfighter, an interceptor or a bomber.

Carrier Battles mod being the prime example of that...
I simply provide Basic fighter hulls, QNP propulsion, and a variety of guns.

If you design the fighter with a small engine, light defenses and a very big gun (or missile launcher), then it is good for anti-ship bombing, but weak vs fighters and useless vs missiles.
If you design the fighter with good speed, light defenses and a large variety of small weapons, then it is great for intercepting missiles, but mediocre at anti-fighter action and completely useless for anti-ship.
If you design the fighter with medium speed, heavy defenses and efficient weapons (as opposed to high damage-per-shot or many small shots) then it becomes great at anti-fighter action, weak vs missiles and weak vs ships.

The player is, of course, free to make a design with compromises between these main types, but since each type has conflicting requirements, the dual-role fighters will be less effective tactically.
(Which isn't to say they can't be effective strategically, due to the fact that having a combo interceptor/dogfighter design means that supply lines are simplified.)