May I float a recommendation for Sea Isle City? It’s got a great small-town vibe going on, and usually isn’t too crowded.
Also, you may want to check out shoobees.com, which is an online guidebook of sorts for NJ shore towns.
Also, a word of warning: Unless you’re at Island Beach state Park (which is also a great place, but I like a bit of town to go with my shore), you’ll need to pay for beach tags. Apparently, this is primarily a New Jersey phenomenon.