Thanks! The first one I suspect is just once the second stage acquires the ship, it'll keep firing if it's a hulk. I'm not seeing the first stage target the hulk or second stage missiles do so, either, unless they're already in the "turn to target and fire" stage.
For the Dragonfire, yeah, that makes sense - the missile guidance operates as if the missile needs to hit the target, not just get within X range. Though I'm not seeing it nearly as bad as what you're seeing; pretty much every point-blank launch vs a Hound locked on fine. Still, I'll keep that in mind!
RE: Hydra, I didn't get a recording of it, but I watched it autofire at a ship corpse. It's possible what happened is that it was triggered by a different ship in range, but the first stage of the missile only appeared to target a hulk droneship.
RE: Dragonfire, probably just a run of bad luck, it seems wildly inconsistent