A good change for the sims?
The game begins after you create your Sim (other sims optional) and they are stranded on and island after a boat crash. The whole game is really a giant free play, you don't HAVE to do any of the goals/tasks set. But after rumaging around the first island for a good hour you may feel you need to get off so there are plenty of resources to use to build a raft and explore. If you want to be picky about it then it can get repetitive: wake up, explore, gather resources, cook, sleep and so on or you can look at it and think this is fun as you find your shipmates, form a tribe, build shelters/houses and thrive. There are also hidden "treasures" spread over the islands to collect such as pirate map pieces or hieroglyphic pieces which lead to rewards for your sim.
Overall, this is a good change for the sims series and it is enjoyable despite how it may look to some people on the box.