As a counterpoint to Cam's comments;
On the other hand, in boats of the size that we are discussing, full keels offer minimally more directional stability than a well balanced fin keel skeg hung rudder boat, (especially since the bulk of tracking ability in this size range comes from the dynamic balance of sails to keel profile, rather than from the length of the keel) and that directional stability comes at the price of much higher helm loads, which can really wear you down and in my experience actually make it harder to use a vane steering
rig.
That so-called seakindly motion comes at the price of larger roll angles which make it harder to move about in a seaway and for some people are more likely to produce seasickness.
With regards to your comments on lighter boats, I would suggest that displacement is a better way to size a boat than length. By that I mean that ease of handling, carrying capacity, accomodation space, and maintenance costs, etc are pretty much directly proportionate to displacement. The heavier the boat, the bigger the sails and the harder the boat is to handle.
For any given person, there is a displacement that they can comfortably handle, more than than that amount becomes burdensome. The traditional rule of thumb for offshore capable distance cruising boats was 2 1/2 to 5 long tons per person (roughly 5500 to 11000 lbs). In a general sense, better
winches, sail handling gear, deck layouts and
ground tackle handling gear have stretched that range a bit, of course there are people whose athletic ability allow them to be comfortable handling much more than that.
Within reason, for any given displacement, and with similar weight distributions (for example ballast to weight ratio) the longer the waterline the easier the boat will be to handle, the more seaworthy it will be, the more comfortable its motion, the more it will be able to carry, and faster it will sail.
In other words, if we compare that Cal 40 to the Hans Christian 33, the Hans Christian 33 is 3,000 lbs heaver, has a lower ballast to displacement, carries nearly 150 square feet of sail area, on a shorter waterline with a greater beam. In other words despite its greater drag (and therefore the need for more sail area) the Hans Christian has less ballast stability and depends on more form stability than the longer Cal 40. The lower sail area, slower roll motion (less form stability) and higher stability should actually make the Cal 40 an easier boat to handle, and a more comfortable boat than the smaller but heavier Hans Christian 33.
In the case of the Cal 40 there is some loss of motion comfort that comes from pitching due to its short waterline length relative to its overall length. To continue this discussion, a boat like the Tartan 37 which has the same displacement as the Cal 40 but a longer waterline than either of the other two and a shorter length on deck, and significantly higher ballast than either of the other two, should offer even greater stability, motion comfort and ease of handling (except that the big
jib, small mainsail
rig proportion of the Tartan 37 doesn't make them as easy to handle as a boat with a more moderate
rig proportion) compared to the other two boats.
And just to put all of this in proportion a boat like the J-40 (J's cruising series) has a longer waterline and way higher ballast ratio than any of these boats, similar waterline beam (greater beam at the deck though), a displacement higher than the Cal and lower than the Hans Christian, and an easier sail plan proportion to handle, should be the easiest of the bunch to handle, offer the most motion comfort, and probably offers the most seaworthiness of the bunch.
BTW I realize all of these are bigger and more expensive boats than Greenboat is looking for.
Respectfully,
Jeff