I will start the thread by confessing to the futility of actually trying to find such a mythical thing as the ultimate family day cruiser, because of the compromises. But here is the wish list...
1) Must be able to have 2 adults and 4 kids on board in a pinch. It would be unusual to have everyone, but it would happen from time to time.
2) Must be able to be towed and launched by a small car.
3) Must be able to be rigged and sailed single handed.
4) Must have a small cuddy (for my family, this is a must).
5) Must be beachable.
6) Must have positive flotation.
7) Should perform reasonably well under sail.
8) Should not flip easily.
9) Should not cost too much.
10) It would be nice if it could handle heavy air.
11) It would be nice if it could double as a weekend cruiser.
The water would be medium size lakes and the NC sounds and coastal rivers (not crossing the open water on the big sounds, though).
I am thinking it would be something along the lines of this at a minimum:
That's an AMF Sunbird; I don't know that it is a good choice, though it seems to meet a lot of my criteria. It's just one of the first few I found in that size that has the seating, cuddy, beaching capability, weight, price, rigging, etc to match my list, though I don't think it really performs all that well.
A few notes...
There are a couple of reasons for wanting it to be beachable. One is just practicality for family weekend fun; it would often be the case that we would camp in a campground at a lake that has public boat ramps that you don't want to use more than once a weekend if you can help it, no docks other than right at the ramp and too much near shore traffic to make mooring a good idea. Also, exploring little lake islands or isolated beaches is fun. The family doesn't want to spend all day in the boat. Another reason is safety. If the weather changes suddenly I want to duck into a cove and pull it ashore.
Cost is always a relative thing, but I am talking under $5K and would love to keep it at $2K or less.
Positive flotation is a safety thing. I would tell everyone that if there were ever a problem you stay with the boat until help arrives or the boat washed ashore. As mentioned earlier, I am thinking public lakes and sounds; well traveled areas and in good conditions (there is always the possibility they turn bad too quick, though).
The small cuddy is so if one or two of the kids is just too tired, we have a spot for them to lay down out of the sun and not underfoot. If an adult could fit, so much the better.