Why should a fuel cell weigh more than the damn hull? If we follow the Korath precedent, it doesn't need a shield generator either-shields should be resupplied on the mothership (as should weapons, like in EV/EVO/EVN). The fuel cell, however, weighs far too much (30 tonnes). Then we'd need thrust, steering, and battery to come in at ~20tonnes. If a fighter hull is 20 tonnes (reasonable, that's the mass of an F-15), it could sport a single blaster (5 tonnes?) or missile launcher (10 tonnes). Perhaps we could reduce the mass of fighter components.
How do we make fighters that aren't garbage, have reasonable specs, and fit into a customizable outfit system?