Couple things... Just bought MY trailer (used of course) for $2000 locally... finding a trailer for an S2 is easy (most larger motorboart trailers work, if the GVWR is over 6000lbs)...
so trailers can be found.
Also I've heard the beef with wanting hull numbers over 400... with the "improved" layups.
My boat has no blisters... its a 1982, and under 100. Comes down to how the boat was used, and taken care of.
I'll totally stipulate the 7.9 is actually kind of boring to sail. It handles most wind conditions quite well, it's almost tame. In that regard I agree, the J is likely a more fun boat, my Crapi certainly was, but it was also slower.
J22, will correct over the S2, there are some conditions they just do better (light air comes to mind, flat water), but in most, the S2 is still faster (as the winds pick up, the S2 just plows on through). The J24, if both boats are well sailed, it can be neck and neck for the entire race. You could easily buy the J24, and be swapping paint for the whole course. But I totally get doing a OD fleet.
If you decide if the S2 is REALLY what you want, PM me.