Re: S2 7.9
I raced on an S-2 6.9 (the smaller sister of the 7.9) for several years in a MORC fleet, and I was very impressed with what a nice small boat it was. Given your criteria (trailer launchable, room for a family, quality boat) IMHO the 7.9 is the only choice you have. Dont over analyze something like "wave action" (you want you boat to rise on the waves anyway, not bust through them). The point is, if you start with the trailer-launching requirement, you aren't going to get any other boat with the range of pluses of an S-2, so accept that your first requirement sets up the necessity to accept some limitations. It seems with an S-2 the limitations are impressively minor.
Certified...in several regards...