If looking for a Summer get together...
Consider a cruise for many to the South Jersey or Ocean City Maryland area.
The climate is nicer than the Bay in mid summer (usually) and it is only a couple hundred miles from either parts of LI, Jersey, or the Chesapeake.
The other way is doable...but then like in the other thread, you might consider it in early to mid October when the weather is still nice and the snowbirders can plan their trip to include it.
I believe some marinas at that point are already charging seasonal rates and in general there may be more spots available in one area.