Good Idea.
I am playing something similar right now. I have a few ideas. But I am not a builder, so I am getting houses from the gallery.
In the moment I am playing a variant, where I started in the stone age. Every time someone learns something in full, or fulfills an aspiration the family can buy a thing, change a lot trade or I can build a lot like a park or a house with other sims or whatever fits in the time. The next generation is the next area. The whole family moves in a new neighborhood or world, all the family members I don't want there, I split from household and put back in the old house. I also build a retail store as a museum for all the collectibles.
My goal is every area one collection has to be full. A full collection allows also for a new lot.
I start with 0 simolions and an empty save File and hope to get rich and have the whole world full.
Then in the future time area there will be a horrible apocalyptic event and basically the sims have to go in a bunker.
All not my own ideas, more or less a mix from different challenges.
Another gameplay I played once, was I made an alien living with the first people. Like a god and immortal. He or she has of course to move to not be discovered, from one household to another and every time is another area. She has to collect all collections and learn all traits. Same here, traits full learned or collection full unlocks new lots....
I also try to make each world a little like one country or continent.
I love generational historic gameplay. I am curios what other people come up with.
