Of course, accepting Jaws 2 does require accepting the preposterous idea that a second massive Great White would attack the same northeast Atlantic town from the first film, and I suppose that's a large pill to swallow. But that fact aside, there are many thrills and nuances to enjoy here.
Take, for example, the acting. The acting is just as good here as in the first. Richard Dreyfuss' Matt Hooper is missed here, and of course you couldn't bring back Quint, but Roy Scheider, Lorraine Gary, and Murray Hamilton give compelling performances just as they did in the first film. Their characters are consistent with the ones introduced in Jaws, and this is as much a credit to the writing team as to the actors themselves. Carl Gottlieb and Howard Sackler appear to give as much care with the sequel as they did the original. You can feel Brody's anger and sense of betrayel in the middle of the film when the foolish town council dismisses him. Scheider in particular really gives it his all here.
There is also a great deal of chills in Jaws 2. The opening sequence, as two divers discover both the shipwrecked Orca and the new shark, is a great scene with which to start the film. The waterski scene and scene with two teens sailing have as much suspense and horror as anything you'll see in the first Jaws. It's true that some of the horror seems more intent on shock value compared to the first, but with any sequel, you sometimes have to up the ante to keep things interesting, certainly with a thriller/horror film.
The use of teenagers as victims in Jaws 2 is often criticized as a way to attract the then-growing slasher film teen audience, and while I'm sure that's true, they still function as viable victims, and none of the situations they're put into seem terribly forced or contrived to me. The execution of these scenes is so good, any such stretches of credibility are forgiven.
I couldn't find any usable clips to demonstrate my points, so please put Jaws 2 in your Netflix queue, purchase from the retailer of your choice, or do as I recently did, check the film out from your local library. If you do, please leave a comment and let me know if you agree or disagree. Thanks!