Most of the timeshares in SXM are not Gold Crown standards. It's a great place to go, but the resorts for the most part aren't that fancy. I would also guess that it's probably early for 2017 high season deposits.
We own at Divi and like staying there. It's got a nice beach, spacious units and was completely renovated within the last 5 yearsa. It's on a peninsula of land with units spread out among many buildings, and I love the views. It's convenient to most places on the island but you do need to drive.
Some people like Simpson Bay resorts and others in that area because it's very close to the busy restaurant and bar area. When I'm in the Caribbean, I don't want that kind of bustle, but that's a personal preference thing. We drive over to eat there but prefer our more quiet Divi location.
I've not stayed at Oyster Bay, so can't comment On its quality. It seems a bit out of the way for us, but people who stay there find lots of restaurants in the area to try. It does have great views.
While it's nice to have a good beach at your resort, SXM has so many great beaches that most people go to different ones several days in their trip.
We spent a week last year in a rental in Grand Case on the French side and that was fun. Wonderful, gourmet dining right out our apartment door and close to Orient Beach, one of our favorites. Unfortunately, I don't think there are timeshares there.