For the most part, Antediluvians never seem to pose a threat to ships I field in combat against them. I'm sure their numbers would make them lethal to smaller ships, but the Auria, which is my current flagship in Uz's Corvus, has an armour rating of around 1500~. It's gonna take a long, long time to work through that armour with frag weapons. The only threatening aspect is the ships with Solons, or Antediluvian torpedoes, which are miniscule and pretty difficult to hit, even for the hailstorm of shots put out by my ship's own Antediluvian guns.
I notice that the Antediluvians have no ship systems yet, and to be honest, I have no idea what would even work for the Antediluvians. Maybe Manuevering Jets, to let them bring their broadsides to bear, while still going at high speeds. Accel Ammo Feeder wouldn't work, they have machinegun-esque weaponry. Fast Missile Racks would only work on a couple dedicated torpedo boats. Phase systems...I don't really picture the Antediluvians with phase technology....Flares could be useful, their lack of shields means that they rely entirely on their agility or a hail of bullets to keep missiles under control.