Thanks for all the feedback!
So, I think right now, I'm down to the 1976 S2 6.8 or a Catalina 25. Both are going to be about the same price. Both have working motors (or so the owners claim - will verify before buying). Neither has a trailer. The S2 is in excellent shape for her age. Sails are still pretty crisp; sheets, halyards, and stays are all in great condition. She had the main, a 110 and 130 jib. No furler for the jib. It was the first time the owners had been to the boat since Hurricane Irene (I caught them "spur of the moment"), and everything was bone dry, but she was sitting on jack stands, not in the water. So I don't know TOO much about the soundness of the hull, but to my untrained and new (though fairly critical) eye, it looked pretty solid.
The Catalina isn't in quite the same shape. She still looks decent for her age, but her main sail has about a 4"x4" hole punched in it, though the jib (which was on a furler) was dirty but otherwise ok. Many of the lines will need to be replaced, but the standing riggig seemed to be in decent shape. The bow pulpit got caught on the dock and one of the supports ripped out of the deck. The cabin was in fair shape, but in need of some TLC (wood needed to be cleaned and oiled, cushions need to be replaced, etc.). Structurally, everything seemed decent, but she hadn't been used most of this year, and it showed. I checked some of the bilges, and found some fresh water in her - probably a combination of rain water from the hole in the bow and water from where the owner cleaned her earlier in the day (though I suspect mostly rain water). Not a lot, but some water. The windows looked like they could use to be removed and re-seated. The owner keeps her with the retractable keel up inside the boat, and he was able to crank it down and up again without a problem. A quick inspection of the cable suggested that it was in decent shape.
The S2 is a great boat, but it's in an inconvenient location, and I would either need to buy or rent a trailer, or sail her a good day or two to get her where I want her. The Catalina is basically where I want her. I'd still like to find a trailer, regardless of the boat, but having the Catalina where I'd likely keep her would make things a lot easier. I "just" need to find a marina at the NJ shore where I can work on her during the winter (or find an ever-elusive, inexpensive trailer for the 25).
Of course, I also haven't given up on the idea of finding a Com-Pac, Diller Schwill, West Wight Potter, or other such 15-16' with a microcabin. But those are VERY hard to find. I had a lead on a 16 DS, but Irene came on the weekend I was supposed to see the boat, and then the owner sold it before I could get there. So, now I'm in this weird holding pattern while we figure out what to do. The added room and stability of the 25 would be really nice. My wife is hesitant because of the boat's "condition" and wants us to find someone in the area to take a look at her, but doesn't want to pay $400-500 for a "formal" inspection. And, of course, there's a 23.5' Hunter about an hour north of here with a good engine, and a good trailer that's arguably within my price range, but I haven't seen her yet. And...