Yeah, if the wife and kids are so heavy that you need the extra 5 kts, you'd be better off with a more powerful plane. Generally, speed exceeding the manufacturer's recommendations for given a phase of flight is not benificial as expected. Drag increases as a square of the speed, so if you have drag, it is increasing faster than anything else, who wants that?
And, no, the fact that something is possible in an aircraft, and a required design requirement to be shown, does not necessarily make doing it a good idea for casual undertaking by low experience pilots.
Pilot DAR