Great reply Killarney! I edited the offshore portions and dropped the redundancy. I can see where you would need everything the extended cruiser would need while expedition cruising (great term by the way. So appropriate).
So what's your take on hull designs? A lot of people seem to speak poorly of the heavy displacement full keel designs. My opinion is that from everything I've read, they tend to really take a beating before they start experiencing big problems. They seem like a good choice for the expedition cruising sailor and even an option for extended cruising. The cruising fin keels with a skeg hung rudder seem more like the design of choice for extended cruising and coastal cruising. What's your thoughts on this? I've read that both types can be dried out on tidal plains for cleaning or repairs. I don't know anything about these bulb or wing keels but they seem much less robust. I'm sure they work well in action but could they take a grounding without leaving you stranded?
I would make more change and say that anchoring and self-sufficiency are needed for both categories. Extended cruisers do not go from marina to marina. From Florida to Australia we stayed at a marina once - in Tahiti and that is the norm, although we did pick up moorings in a few places like Bahia, Ecuador (we left the boat for a month to go backpacking), Bora Bora (it was free and well placed), and Vanuatu (poor holding and they were not too pricey).
Hull forms - hmmm, sure to start an argument. I think that the ideal would be some form of longish fin with a skeg rudder. Everything is a compromise of course. As well as the hull form there is the question of displacement. Most long-keeled boats are heavy displacement and most narrow fin keelers are light displacement but that does not mean you could not have the reverse, but they are just really rare. Cost comes into the equation for sure. A lot of people are cruising in full keel heavy boats because they can afford one of those from the 1960s to 1980s, not because they are ideal.
It would be very instructive to have a dozen exprienced cruisers with unlimited budgets sit down with Bob Perry or another top designer and have a custom boat designed. I imagine you might get quite a lot of variation in the result.
Another consideration is hull material. The expedition cruisers are going to lean more to stell than the extended ones (although there are lots of steel boats cruising in the tropics). Many years ago when we were cruising in Newfoundland we met an American couple going home from a cruise in Labrador. They had a Mason 43 which is a very heavy, solid boat but were going to sell it to get a steel one because they wanted to cruise to Baffin Island and Greenland. In remote places like these (even in some not so remote ones) there may be one (1!) sounding in the bay that you want to anchor in. The chances of hitting something (and it will be rock on Baffin Island) are just too great.
Wing keels are a non-starter for me because of the problem of getting hung up on something. With a fin or long-keel you can take a halyard from the mast head to heel the boat and reduce the draft so you can kedge (or get pulled) off. Can't do that with a wing so a reasonably minor, non-damaging grouding can quickly become very serious.
Someone mentioned the CE Ocean classification. I would not put too much belief in these. The specs for the rating say that the boat must be able to take 4 m (13') waves and force 8+ winds. I have no idea what the '+' means but I assume not force 9 or they would say so. We got knocked down, well in the tropics by force 10 and 13' waves are not that unusual at all. We try to avoid them but don't worry too much about a forecast until the waves are over 12' and we are sucky cruisers, like our comfort.
Should put a plug in for our boat. It is a Ted Hood designed, heavy (36,000 lb) centerboarder (5' BU/ 11' BD). The centerboard adds a complication (got to change the cable before we take off again) but means we can get into some pretty shallow spots and still go to weather like crazy. The board also allows us to balance the helm which is big help to the Monitor when the winds get up over 15 knots. Hood was a genius with these heavy centerboard boats (built as real cruiser/racers - ours did a Newport-Bermuda Race and then carried on the Med), but such boats are not built much any more because they are quite expensive to build and no longer competitve as racers - but very good cruisers since they were built to sail well and not beat a racing rule.