All they need is to change the VFR minima upwards so people don't end up trying to scud run in crap weather rather than go IFR.
EGPWS is impractical at low level in a helicopter as the amount of alerts just lead you to disable it.
Definitely need CVFDR and the best additional equipment would be a rad alt with an audio warning - that, however, requires the pilot to set the bug religiously and react to the warning appropriately.
Stop pilots scud running and we will see a reduction in CFIT and IIMC.