1. anything at the other end of a 6,000km hole is not an imminent threat
We don't really have enough information about the aliens to make this assessment, I would argue. Maybe they're all on hoverbikes. ;-) Or can teleport up the tube like their queen once awake, unless drowned first. I appreciate that proper SF would have bothered to explain how this was going to work, but in a James Bond underground-base-style denouement it's enough that we know the aliens are going to pose a threat once they get out, and that whenever they arrive it'll be really really bad.
2. emptying the Thames into something that size isn't going to make a noticeable difference to anything
It won't fill the hole. It could certainly fill the spaceship at the bottom of it, which I assumed was the point.
there's the Huon particles,
The Huon particles are, I agree, arbitrary and problematic. They bother me a bit more than the stonking big hole.
and oh, pretty much every emotional arc in the piece
no subject
We don't really have enough information about the aliens to make this assessment, I would argue. Maybe they're all on hoverbikes. ;-) Or can teleport up the tube like their queen once awake, unless drowned first. I appreciate that proper SF would have bothered to explain how this was going to work, but in a James Bond underground-base-style denouement it's enough that we know the aliens are going to pose a threat once they get out, and that whenever they arrive it'll be really really bad.
2. emptying the Thames into something that size isn't going to make a noticeable difference to anything
It won't fill the hole. It could certainly fill the spaceship at the bottom of it, which I assumed was the point.
there's the Huon particles,
The Huon particles are, I agree, arbitrary and problematic. They bother me a bit more than the stonking big hole.
and oh, pretty much every emotional arc in the piece
Que?