I would like to be able to sail some distances, though, and to cruise for as long as a week. And I definitely must be able to single-hand her.
IMO that narrows it down to 30-36 foot range, big enough for 2 but easy enough for one person with some experience to handle in heavy weather.
Lots of good choices here. If I had a budget in the higher end range (50-60K) I would go for something like Tashing Baba 30 (one example here: 1980 Tashing BABA sailboat for sale in Georgia
) or better yet Kaiser 34 Gale Force (example here: 1978 Kaiser Yachts Gale Force Offshore Cutter Sail Boat For Sale -
For lower end budget (25-35K) I would get a centerboard design, like Pearson 35 or Bristol 35 - lots of them around, in decent shape and with decent gear.
Allied Seawind 32 is also a good choice, as well as Cape Dory 30 to 36. All rock solid, conservative designs that will not let you down in bad weather.
I would not hesitate to take any of these boats properly equipped across any ocean.
Some of these boats come with a ketch rig which I personally like. Yes, they are more complicated, but they give you advantage of flexibility when single handing, especially off wind, and are great when tacking often in narrow channels. I would not look specifically for a ketch rig but would not hesitate to take one on an otherwise good boat.