I'm not sure it would be faster. After all, it uses the same armor thickness, which is the primary reason that the Cataphract is noted as being slow. In addition, no mention is made of faster engines.
If Cannala's ancient mines & torpedoes are so effective, maybe we should design our own minelayer?
I think that may be a good idea.
Charybdis Magnetic Mine The Charybdis is a heavy, tethered mine. With a warhead significantly larger than our current torpedoes, it is capable of destroying all but the largest ships outright. It's magnetic sensor detects changes in magnetic field, rather than absolute field strength, making them more sensitive and harder to fool. A build-in counter can be configured to allow a certain amount of ships to pass over unharmed. This makes minesweeping far harder, as many swept areas still contain mines. Though it's rather heavy, the Charybdis can be deployed by a modified Salamander parachute from the Reckless effect or Ice Giant in addition to various forms of naval deployment.
Whalesong Acoustic Mine The Echo is a heavy, tethered mine. With a warhead significantly larger than our current torpedoes, it is capable of destroying all but the largest ships outright. It's accoustic sensor listens to the sound of nearby ships, and is both configurable for broad ranges of the spectrum (blowing up everything) or clearly defined frequencies (blowing up only certain classes of vessels). It includes a build-in configurable delay counter to allow a few ships to pass over unharmed. Though rather heavy, the Echo can be deployed by a modified Salamander parachute from the Reckless effect or Ice Giant in addition to various forms of naval deployement.
Electric Eel The Electric Eel is an advanced naval torpedo, weighting almost 2 tonnes. It's equipped with an accoustic sensor, which activates after a certain distance has passed and then homes in on a nearby sound signal. Selective dampening ensures that the weapon does not try to follow it's own propellor or that of the launching vessel. The heavy warhead is triggered by either an impact or a magnetic influence detonator, depending on configuration.