I play on rotation so I have a lot of different 'stories' going on. Here's a few:
Loner guy in astronaut career, who is obsessed with finding proof of alien life. He's gonna build his own rocket ship and visit the aliens and will eventually bring one home to marry and have little alien babies.
Orphanage run by a mean criminal lady who hates kids. All the kids have to do all the cooking, cleaning, laundry, fixing. They are banding together to become a family in spite of their carer and will one day exact revenge on her. Possibly a bit too dramatic for you though.
Two couples living next door to each other, both with twin toddler girls. They are gonna grow up to be best friends for life.
An off-the-grid couple who live in Glimmerbrook, they are trying to make their own furniture, grow their own food etc. Starting out with next to nothing, so kind of rags to riches.
I have a couple, one in the military, who are doing the Strangerville mystery.
A female sim who left her horrid husband and had nowhere to go, she got a job as a live-in nanny to look after a family's baby and toddler. When they aged up, she moved in with another family to be their nanny. Then she discovered that this family were vampires and, after letting the dad feed on her, she started falling in love with him. Maybe miss out the drama bit from that story lol.