Nice shot brendan, nice that you've managed to get some pink in there, mine is all blue (modified vs un-modified cams).
DSLR lack of dynamic range???? Are you for real?
You've got a 40D right, 14bit, that's not bad you know ... ever tried slide film, or 8 bit or even 12 bit?
The only thing that has more dynamic range is 16bit astro cams! Anyhow, curves in conjunction with layers are the way to go, as you pointed out