MJ i agree with everything apart from the dry suit recomendation.
A neoprene dry suit is very bulky and will hamper movement in the cockpit. Flooded it gives you no more thermal insulation as neoprene works as an insulator only when water is trapped in a VERY thin layer direct against the skin. A neoprene dry bag does not work that way. One of th greatest fallacies in diving generated I suspect by Northern Diver to sell the 8mm "commercial" neoprene suits in the old days. In the older days we wore these suits with a 2mm neoprene wet suit and and pumped hot water into them from the surface via the nemo umbilical instead of air.
A membrane suit with a thinsulate under suit will keep you warm even flooded (5hrs deco in a flooded membrane bag in norway.....) and is no more bulky than normal clothes and a coat.
I wear a goretex mix boating dry bag with a weezel undersuit for long sea crossings. This is waterproof to 5m but breathes through the goretex so keeps you comfortable on the flight. I have the latex boots and wear 5mm neoprene boots over them. Very comfortable even on a very long flight.