I think with all the muddle in my head, I've lost sight of the obvious. Particularly the point of not counting on high numbers but still dealing crushing blows when they attack.
Implementation is already beginning.
Another update for the Keepers of Amun, the Harbinger.
Staying with the sceme used for the Vaygr and Hiigarans, the Harbinger gets a weapons choice, the Plasma Battery designed for disabling its targets, allowing the main cannon to target them more efficiently while the Ion Cannon allows it to deal more damage to its targets but lacking the disabling effects.