crab, I know what you're talking about, but all it takes is a bit of re-caging your brain to what a "stationary" hover is. If you center the cues and the hoist operator keeps telling you to stop right, then you figure out that a left drift is required to stay over top the raft. I've found the more I do night water, the less I rely on outside references and the more I rely on hover cues and the back-end talking to me. The normal hover height for a hoist is 40ft for us. I started using the higher heights in the Gulf of Mexico, where the waves are very small. Rotor wash seems to be a bigger problem in flat sea conditions than it does in higher sea states. Although I will admit, my experience in heavy seas is only about 3 months old.
My hover coupler comment was intended to reference the systems where the hoist operator actually controls the aircraft, of which I actually have zero experience since our system is basically an Atari brain and very poor at holding a hover.