I know Anize recommends the Orthrus (though lists the Onyx as a “safer alternative”), but I’ve always followed Jori McKie’s recommendation and used a passively tanked Gila. Even with only moderate skills, I’ve never had a close call. Occasionally, the Ashimmu eats all of my T1 drones and I have to reload from my emergency stash in the cargo bay, but that never happens until after the escorts are down, so I’ve never been in danger of losing the ship.
But, to your point, even Anize seems to run a profile similar to what you described with 10 missiles on the first escort and 8 on the second.