Space Themes?

All the above. I remember them talking about designing a Sims Spacepack back when I was playing Sims 2. I was so disappointed when it didn't happen. Space Colony was the closest thing to it, but it just wasn't The Sims. Oh, and I love the Batuu pack.

To terraform a planet would be fun, building and gameplay on a mars like planet

I would like another liveable planet, it can either be sixam or another one, i would also liek new aliens to play with, and lots of new objects and build mode items :)

Ok, I'm so picturing a new World Planet that's part Gallifrey, part Starfleet, part Alpha Centuri & part Capa. And it's a livable world, not a vacation world with about 20 lots 5 neighborhoods. This world would have actual flying speeders, beaming technology, Klingons, Vulcans, Daleks, Borgs, Time Lords, etc... ;) :p

I actually like all of the ideas. I would love to be able to build on Sixam but I would also like to have other planets and aliens. Sixam should be able to be unlocked as a neighborhood and from the planet part we visit there should be a secret portal we unlock that once we go through it we unlock the Sixam neighborhood we can build on. Same with other worlds. We should have other planets as neighborhoods.