If all you can get, from your fish purveyor, is frozen crappy scallops then it is time to find a new fish purveyor. I always try to buy "dry pack" scallops. For more on those see this discussion:http://www.cheftalk.com/forums/showthread.php?t=19096
Both sea and bay scallops can be some of the best eating around, or they can be real crap. It really all depends on how they are processed. Take the time and search out the good ones, though they don't come cheap. And frozen doesn't always have to mean "crappy". I used to buy scallops direct from a Boston supplier that made no qualms about the fact that they prefered to freeze their scallops immediately after processing rather than treat them chemically like many processors do. They are still some of the best scallops I have ever gotten. The most important thing is to find a fishmonger that truly cares about his/her product, knows where it comes from, and how it is processed.
As for Nantucket Bay scallops, we used to look forward to the opening of the season there, on November 1st, with great anticipation. The harvest used to only last a month or 2, though now I believe it has been extended. These sweet little morsels are like candy from the sea. Very flavorful, sweet and tender.