I would definitely like a Difficulty setting in game.
Some people like to play as an easy Sandbox/Creative style game, and others like to play the game as a Management Simulation. It seems like the Sims team only caters to people who want the game to be a casual, sandbox game, and not to people who want the game to be more challenging.
If we had different Difficulty settings for the game, it could satisfy everyone.
And no, I don't think Lot Challenges will magically solve everything. I can't imagine how annoying it would be to have 20+ Lot Challenges just to make the game challenging. Lot Challenge for burglars, Lot Challenges for disease, Lot Challenge for higher Skill Difficulty, Lot Challenge for Lower Wages, Lot Challenge for Daycare costs, Lot Challenge for Higher Bills, etc.
It's too much! Some of it just needs to be controlled by toggles. Where the heck are toggles for this game? It's been 7 years..