These are some interesting ideas, and I will comment on many of them.
1. 90's Sims- This could fit into a Sims 1 remastered, if they go back and re-make the first sims game with the advanced technology. Some would call the styles dated, but if they put some real thought into doing this, it could be done well. They could always add extra content, plus cc, which would make it feel more modern.
2. Several of your historical ideas would be sim-ified and added to a less historically correct version of the game's history. This would involve writers creating a detailed, yet sim-ish version of history, then it being made into a game. Like Sims Medieval was story-based, it probably would be too. I might see a Colonial era thing done, because you've got Pirates, and native sims to add spice. And because I can see the makings of a story behind the Sims settling in Sim-nation. Otherwise, the Classical era, because you don't need to be as historically accurate. There are probably a lot of little stories in the legends/histories that are less well known. Otherwise some of your decades could be fit into a regular Sims stuff pack. We cold get 1920's style clothing and some more Art Deco style furniture. I think that was the style that was popular back then. Of course they'd have to add something to bring gameplay, I don't know what that could be. And they'd have to fix the glitches with round walls, finally, because such are popular with this style too. But it could be done.
3. Your Science Fiction ideas are cool. I've tried to build a Space-ship type lot in the Sims before. Unfortunately, with the Sims as it is now, it makes that hard without a massive break in reality. This could be fun. If what I heard about Disney wanting to buy The Sims, or a portion of EA, is true, we may be seeing Star Wars The Sims eventually anyways. Of course within the Science fiction world you have different styles as most is based on whatever imaginative story first got us into the genre. There are your Star Wars fans, your Star Trek Fans, your Steampunk fans, and many more. Does anyone remember a little show called Farscape? Stargate SG-1? The Best version of a science fiction life sim would somehow enable us all to be satisfied and to build worlds/ships/planetary bases around it.
