Louis - I see where you are coming from but the weak link in your proposition is the pilot - no matter how good his autopilot and 'fly through' modes of operation are - he can't see what is happening beneath the aircraft and so any response of his is 'lagged' by the time the winch op recognises and verbalises the correction required.
The winchop's Hover Trim on the new aircraft will give him sufficient authority through the clever autopilot to move the aircraft precisely to assist the winchman.
There is often some manoeuvering required for a night wet (or day for that matter) as the winchop needs to keep the cable in such a position that it doesn't hinder or endanger the winchman or casualty whilst the casualty is prepared for lift.
The pilot can establish the aircraft in an autohover and then verbally give control to the winchop - I don't think this will be done any differently in the new aircraft, they just won't have to fret about doppler mislocks or spend ages trimming the aircraft to a relative hover.
All the new technology is in the aircraft, not where the winchman is working.
BTW the 3A Sea King, although still doppler based, has a more flexible, digital SN500 AFCS with few of the limitations of the mk31 FCS I think you are remembering.
Out of interest, on the Bristow roadshow the accuracy of the autohover was stated to be such that it could keep the aircraft in a 1-metre cube of space - that is impressive but still not accurate enough for precision winching and it is still only a datum from which you have to manoeuvre to compensate for wind, tide, downdraught, sea movement etc. I know you can give it vectors to compensate for steady state drift, for example, but responding to a messy sea with random waves breaking is beyond even that tech.
New technology is great but it isn't a panacea for SAR.