Julian,
Congrats! We are just up the Rt 73 from you in Marlton. This season will be our 6th season at SJC. Our son was 7 when we started and is now 12. We chose SJC mainly for him. I understand getting your kids to love boating is one major route to boating longevity. And he loves it.
We are in J dock. After spending our 1st season in Wildwood, NJ with an Express Cruiser, the relative open/deeper waters of the Sassafras, no greenhead flies or no-see-ums, and frequent no-wakes on the ICW, SJC and the Sassafras have been great. With smaller children, the drive (about 1.5 hours from Marlton) is just about right.
There is now no-smoking at Signals (as is the rest of MD I guess) and we have limited going there because there was no separate smoking session really. But, we intend to go more often now.
Annapolis and Baltimore are each a 2 hr cruise from SJC at 30MPH.
But, you will get plenty of advice from your new friends at SJC on all these.
Good Luck on your first season.
Joe