I've optimized the scene to a
satisfying degree.
This took 27 minutes and 30 seconds to render, 318% faster. Almost
as faster as blender internal, and much better looking.
Unfortunately, it's still too slow for a full 1080p render.
Fitting with the "whoops" nature of its start, the finished product
came out at 100 fps, rather than 25, so it's four times faster than
it should be. And, of course, the vimeo codec obilterated all the
fine detail. Oh well.