'ideal' is hard, north norfolk is stunning and open, north devon for beaches and surf fun but we have recently been converted and were surprised by Littlehampton. It was 'ideal' because the coast and beaches were high quality and sandy, it was easy for us to get to and there were lots of other places for us to explore (such as Arundel castle) so it had something for the whole family. So 'family ideal' littlehampton, personal ideal...little village called 'Winterton on sea' in Norfolk

Sussex by the Sea; Arundel, Bognor Regis, Littlehampton & Sussex Downs