In one of my saves I only answer to my Sims whims. There is no story. The game tells you what to do. Move a sim onto an empty lot. Cheat money to zero. Start collecting and be homeless for a while. Sim gets a whim, lock it and complete it. He gardens, paints and writes for money completing aspirations along the way. Main goal is to complete the money aspirations. I play with aging off but I wonder if it could be done on a long life span starting with young adult.
Thinking about trying the one room challenge ... maybe soon.