A few sandbags piled on the deck beneath the aircraft would have meant that had the ship pitched up, or the helicopter pitched down, the personnel underneath might have less chance of having their grapes pressed. Apart from that, it's a good plan as far as I see it; the S-76 u/c failure procedure in the checklist we used was similar except we stayed in the low hover due to less u/c height. We practiced it a few times and it worked fine.
I don't see see any great advantage in having everyone in radio contact as long as visual signals could be used instead.