Pearson 39-2/Ericson 38-200/Tartan 37
D, altho'' these boats seem to fit into the same niche I think they are substantially different WRT your plans, short- and long-term. And BTW congrats on deciding to take a year off with your young family and spend it cruising; it''s an experience that you will share together for the rest of your lives.
Here are some issues I''d suggest are of primary importance to you - again, given your plans - some of which are more generic than boat-specific:
1. These boats represent a wide range of cost, especially when you factor in both age-related work & upgrades for cruising. Re: cost, there are apples and oranges here. Were I you, I''d want to have a very firm financial plan (WRT total boat cost, cruising kitty, and re-entry budget) before making a boat choice.
2. Your short-term plans are somewhat mutually exclusive with your long-term ones. Cruising full-time places a premium on space, tankage, convenience hardware, load carrying and the like. Your longer-term plans are much more forgiving re: the capabilities of the boat. I could see a logic develop where one set of plans shapes the boat choice and leaves you with regrets for the others. Since you can have an enjoyable cruise on many varieties/sizes/types of boats, my bias would be to place an emphasis on what boat would better suit the family (and then empty nesters) longer term. The point is : Where should you place YOUR emphasis?
3. You seem to suggest a keel/centerboard choice is important, but are considering boats that have fixed draft keels. Again, what priorities do you have?
4. The Pearson you are considering was built after the brand was purchased out of bankruptcy and then built for only a few years before going under yet again. In your shoes, I''d like to better understand build quality as it relates to the age of construction; the ''New Pearson'' was not well funded near its end.
5. We all have our own ''design'' priorities and I think it''s important for ALL of you to have agreement on what yours are. To illustrate, the P39 features that our live-aboard cruising lifestyle would put a premium on are a dedicated chart table (it''s amazing how much homework, laptop work, emailing et al. gets done there and an ''end of the settee'' chart table without a backrest is a poor choice, IMO), a functional galley (all your choices offer this), and a quarter head adjacent to the companionway. But I''d also add a dedicated shower stall (especially with your clan aboard), something the Ericson offers but the Pearson lacks.
6. All these boats are going to be showing their age, so I''d make up a list of key equipment that will result in either a large amount of additional expense OR insurance against it, and then use that list to vet candidate boats. E.g. a new engine and relatively fresh & diverse suit of sails would be at the top of my list since they''d run $15K and $10K respectively. In 2nd place would be self-steering; you''ll be short-handed and caring for kids, so bullet-proof self-steering is an essential; figure min. of $6K. Fresh rig, canvas and cushions would all be next as they are all essential to comfort aboard, in one fashion or another; they each represent about $3K. I''d not put electronics on my list; cost is lower, you have diverse choices to fit your budget, and newer is better.
7. Personally, I''d try to keep in mind that people usually buy more boat than they actually need (more space is always a luring feature...) and that actual expenses usually end up being larger than planned (which also argues in favor of smaller=better). I think this is doubly true after the cruise when your use level drops.
Two ancillary comments about the designs:
1. The T37 will be much more comfortable belowdecks in hot/humid summer conditions than that sweat box aft cabin in the Pearson, embraced by the hot engine
2. Balsa cored hulls always invite worries, and yet some builders really seem to have understood how to build them well. The Ragles did a Circle in their T37 TIGGER without any core issues; ROUSER did a SoPac run from California without problems; and many T37''s have done Atlantic Circles. Tartan seems to have done their cored hulls very well. I notice no one is whining about Hunter coring their hulls these days (and worse, using plywood for their decks) but of course the problem is what condition YOUR new/used boat''s hull will be in. All things considered, a non-cored hull on an older boat is probably preferable.
Good luck on the search, and on all the fun that will follow...