Thanks for the welcome, Tom. To answer your questions ...
What extent of a rebuild? I don't really care. If the hull and deck are in good shape, I'll just redo the interior. If the hull/deck are bad (blisters, delaminations, big hole!), that's fine. I'll just build a new hull (strip/cold-molded). One of the things that I realized when I considered building from scratch was how do I acquire/produce all the fillings that are unique to the boat (e.g., stem fittings, rudder, ballast keel, etc.)? So I guess that the minimum requirement would be that most of the key components are included.
What about other designs? Sure. I would consider any boat of a good pedigree in the 32-42 ft range. So why these particular designs? What can I say, they're just beautiful!
-Denny