Kroom By using these fighter i was able to destroy both ships by using only a fraction of the money, those ships use a lot of money in propulsion but even so is not nearly enough to keep these fighter away form them:
The game doesn't spawn homogenous swarms of small ships in high level systems, and doesn't coordinate ships. If you're only interested in MP there's an attention cost to large numbers of small ships because you can't just pause for minutes to give them all orders every time something changes. There's also the ring of death which magically kills kites anyways so it's not a relevant context for balancing long range weapons.
If you made Bounty Hunter spawn thirty Stalker2s in place of a tier 9 ship they would get pulled a few at a time by anything with more than 250m weapon range because they only have fighter cockpits and AI ships don't share vision radius.
In actual play you see maybe two Kilrathi fighters (why never the human stuff or anything original or from other settings?) in a clump with larger ships and can easily avoid fighting them at the same time because of their short aggro range.
Comparing that fighter to other capital ships suggests that it's the fighters that are too strong not the capital ships that are too weak. Running them in battle helper with a movement order to get them into sensor range they beat too many of the design contest winners. They don't decisively beat Excelsis, which tricks the AI into sticking fighter after fighter right in front of its flaks while shooting at armor and stuff irrelevant to the fight and they don't beat the Marathon because after it breaks apart they target the almost harmless and difficult to kill section with a control room and let the missile sections pick them off with impunity.
Fighter guns appear to have mostly fair tradeoffs compared to the vanilla laser blaster only if the value of a crewman and small volume are ignored. The narrow arc and short range are a fair trade for the higher shot speed and the greater price per damage is a fair trade for the higher energy efficiency, but being 2 tiles smaller using 1x1 or 1x2 bunks and 1125 or 1325 credits cheaper depending on if adding crew space would necessitate adding a door. The second tier fighter guns have a further compactness advantage doing damage more comparable to weapons that are either many times bulkier like the large laser blaster or that require an ammo factory. You may have overvalued firing arc, but firing arc has very little relevance on the sort of ship they're intended for. It's wide enough several can focus fire on a single tile, the availability of side mounts and the ability to fire through armor duplicate the advantage vanilla laser blasters and electrobolts get from their >180 degree arcs. The narrow arc imposes little drawback. I'm pretty sure you've also undervalued armor, possibly because the mechanics have changed since you introduced the guns. The low HP of fighter guns may be intended to compensate for being placed behind armor, but something behind a 800 HP 2x1 armor block or even a 400 HP 2x1 wedge is more durable to explosive and penetrating weapons than a 1200 HP standard cannon against explosive and penetrating weapons.
The ability to beat most capital ships with guns renders the single shot torpedoes and the larger, more vulnerable weapons like the fusion cannon and plasma lancer obsolete. If it were just Walt's and David Billingsly's and mine I could chalk it up to poor or overly aesthetics focused designs. If they were losing to bombers or big gun fighters that would be the point of torpedoes and big guns, but it's winning using nothing but the 1 tile no crew fit behind armor guns.
TLDR: Overpowered fighters being able to beat overpowered mass driver kites does not make mass driver kites not overpowered.
