I love having a bunch of different worlds to explore, but there's a limit to the number of sims the game can handle and probably a limit to the amount of space taken up by worlds and lots. In Sims 3, you chose a world, and that was where your Sims lived. If you moved them to a different world, the old one was deleted. You could visit vacation worlds and university, but as for home worlds, you had one at a time.
People have already complained that the worlds we're getting in packs are small, that they don't have many residential lots. I think that's the price we pay for having so many worlds in total. I enjoy getting new worlds, and being able to create my own would be fun, but that's kind of what they gave us Newcrest for. I know you can't decide where the lots go or sculpt the land or decide what the background looks like, but Sims 4 has always been very stripped-down. That's what a lot of people like about it.
