Douglas, how much difference do you perceive in both opportunity and complexity in planning and executing a weekend at the lake (say 5-6 hours in the boat) vs. the equivalent use of the plane? How do you view the limitations of each? What is your family's attitude about the two activities?
I do my boating in the Gulf or previously in the Atlantic so cannot consider lake boating from recent experience. As for the opportunity for boating and flying, and executing the said trip, the amount of time spent is for planning and preparation is probably less for flying but is different in what is done. When I plan a day trip with the plane, I check the weather the night before(computer when I file my plan) and right before I leave to go to the airport(about a 10 minute drive from home). I drive to the airport. Get the plane out of the hangar, do a preflight, wait for opening my flight plan if IFR, taxi to the runway, and take off when cleared. About 30 minutes or less of prep and travel to the airport, and another 30 for the preflight, and taxi to take off. Boating I check the weather the night before, and before I go out(usually the forecast on the weather channel, or local news. For a 2 or more hour boating trip I need supplies(food, drink, and ice). So there is the trip to the grocery store. Then I have to get the boat in the water...I am lucky it is on a lift in the backyard, check the boat out(abbreviated preflight), get everyone on board, and off we go. As for my family I am about as likely to get my family boating with me as flying.
Now if I did not have my boat in the backyard, then the preparation for boating is probably a lot more time intensive. Still need the food and supplies, but in addition, now you have to trailer the boat, get the boat off the trailer, park the car, walk back to the boat, etc.
To tell you the truth, for me, spending 3 hours on my boat is A LOT more work, then spending 3 hours on my plane. Also after flying, I spend at most 15 minutes getting the plane into the hangar, and cleaning it, whereas boating is typically over an hour, between get the gear off the boat, cleaning the boat, and putting the canvasses, etc back. Fueling the boat is much more time intensive than fueling the plane. My boat burns about the same amount or a little more fuel an hour than my plane, but then again my boat is 25000 lbs doing 25 to 30 knots, and my plane is 3000 lbs doing 130+ kts.
So for me boating tends to be a lot more work than flying.