You sounded like me 4 years ago. I was 21, took a town sailing course and fell in love. Read every single book I could and sailed every chance I got. My first boat was a 25 ft Mark 25 and used it just about every day and weekend for the summer. What I quickly realized was that I outgrew it in that one season since I used it and loved it so much. I wanted a bigger boat because I loved doing the cruising thing so I sold the Mark 25 during the winter and bought my now current boat a 32' Morgan 323.
So depending on how quickly you learn and get used to things, I wouldn't rule out boats over 30' especially if you are cruising with 4!. It may be a little bit more to get used to initially when it comes to things like docking and maintenance but you will really enjoy the extra space. Although I love my boat and am 150% satisfied with it, if I won the lottery I could easily move up to a 40ft+ in a heartbeat as every time you see or go on someone else's bigger boat, yours feels that much smaller.
But Long Island Sound is a great place to sail and cruise and I wish you luck. Just curious, what is your budget?