Gulfstars for Cruising?
Chas, I don''t think there''s a major flaw with the ''one [compromise] boat, forever'' scenario; it''s tradeoffs are pretty straightforward. It presumes many assumptions you make on the front end, which may/may not prove true...but it also has numerous potential benefits. You just have to accept the risks to gain the (hoped for) benefits.
Given the designs you mentioned, it''s no wonder your wife is attracted to a wide-bodied boat like the G37 (or even, oh my gosh, the ''shipping crate the other Gulfstars came in'' G36). A D35, T34 (the 70''s S&S centerboard design, I assume) or P35 are all in a different league re: liveaboard comfort, storage, etc. All the above designs are definitely not suitable IMO for comfortable, indefinite live aboard comfort nor for the load carrying ability that real blue water sailing can require.
But fundamentally, you seem to be asking about the ''fat/shallow'' hull forms and their desirability vs. liabilities as a blue water boat. While we haven''t owned a Gulfstar, I think WHOOSH fits into your ''tradeoff'' category and so perhaps a few comments about our experiences with her would be worth sharing.
(BTW I don''t know how you come to the conclusion "We will probably be using Trinidad as our home base and the only true hurricane hole there allows drafts of no more than 5 feet or so to get into it." First, there are no ''true hurricane holes'' in Trinidad; they have had some real stinkers down there where boats have been beat up everywhere. Moreover, shallow draft is not mandated by Trinidad''s coastline. Chag Bay''s anchorage is deep, slurpy and crowded. The bay to port on entering the Dragon''s Mouth (Scotland Bay, as I recall) is like a fjord with deep water and limited shelf space for anchoring. Perhaps you are referring to the bay & mooring field known as TTYA which was created by the manmade isthmus which also closed off Chag Bay''s anchorage. There are shallower areas there but the field is very large and one can also anchor, close in or farther out, so shallow draft is not a requirement there, either. I really don''t associate shallow draft with Trinidad at all).
As you know, variables like the general hull form, keel & rudder choices, the size and design of the sail plan, the design & build of the hull/deck monocoque structure, and the displacement, waterplane at heel, and other variables all contribute to a boat''s performance at sea...and that''s before considering draft. We''ve owned two intentionally-designed shallow-draft boats, an Enderlein-designed H-R 35 (27.5'' WLL and only 4''3" designed draft) and our current Pearson 424 (33'' WLL and 5''3" designed draft), and both boats have been comfortable at sea and neither seems to exhibit any squirrly behavior. However, I attribute this to the overall nature of the two designs; it''s hard to carve off ''draft'' as a limitation all by itself re: seaworthiness, motion comfort, etc. (Also, keep in mind that we cruised both boats with deeper draft: our H-R 35 ended up with 5'' draft after the family moved aboard & we sailed for the Caribbean; WHOOSH grew to 5.5'').
Predictably, where I think both boats suffer due to their draft is in the area of windward sailing...but even here, it isn''t easy to isolate the issue to draft alone. The H-R''s secret to good windward speeds was her narrow hull (10''), the resulting narrow sheeting angle, and decent WLL, even despite her limited draft and consequent leeway. OTOH the 424 is a beamy boat (13'' max beam) and the genoa tracks are w-a-y out on the caprail. Couple this with her (normally)ketch rig and shallow draft, and the tactic mandated when going to windward is to keep her on her feet and not ask for more performance than this combo of factors can deliver. This in turn means keeping the sail area suitable for the wind strength (to give perhaps 15, preferably not 20 degrees of heel) and that reduces power and therefore speed. I don''t think it''s surprising that, in both cases, the designers gave these boats big engines...and I''d want that same attribute in other shallower draft/beamy/loaded down sailboats I considered.
Re: Gulfstars generically, I think your bigger issues are build quality and age vs. condition. Our homeport is where Gulfstars were built and listening to some of the stories from ex-employees can be pretty funny but also troubling; these boats did not all see the same workforce, get the same amount of materials, nor attention to detail and so a survey is critical. And then of course, there''s the issue of a 20-25 yr old boat. If you have her for a lengthy period before you start cruising, you can invest yourself in checking (e.g. chainplates, rudder), replacing (old pumps, lights, electronics), upgrading (fresh engine, rig) and customizing (for your liveaboard needs & tastes) before you head out. This can actually be when the cruising really begins and some people like a big dose of this. Others find it purgatory and lament not being able to sail and learn the boat because all their time (let alone money...) is poured into her at the slip. But that''s just something you''ll have to gauge for yourself.
Good luck on the mulling and choosing...