Is this civilian ops only?
In addition to Shytorques questions which would paint a picture for us to offer specific suggestions, what about:
NVIS?
CRM?
Over water at night requires a minimum of FULL auto pilot and an IR pilot. Anything less is asking for trouble.
When you arrive at scene and during the descent to the hover, at night, no visuals, is it automatic doppler hover? A visual approach to the hover is asking for an accident.
Local night overland EMS should be flown to CASA night VFR limits, is it?
If CASA aren't doing their bit, then you're going to have to lobby it as a unique group and stiffen the minimums. Do you employ GPS approaches at night?
Give us your reasons why so many of you 'stoof' at night???
Regards....