If we look at the majority of HEMS accidents, we see most of them happen at night in less than ideal weather conditions, and when returning from dropping off a patient.
People run into things they can't see in time to avoid.
Fitting a TAWS system with accuracy suitable for helicopter operations would help prevent that (it's been done in tour helicopters in Hawaii, and they're definitely VFR)
Making people fly dedicated routes with specific altitudes at night would also go a long way to reducing accidents.
And didn't the FAA just change the rules about what visibility requirements are at night??? What happened in this accident vis-a-vis those new rules?