If I absolutely have to pick just one, then it has to be option #1. It's by far the most comprehensive and the national obesity rate mechanic, as it stands currently, is rather underbaked, so it could very much use being expanded upon.
I also like the home upgrade stuff you mentioned in option #3. That being said, I still would love to see my ideas concerning mobility scooters being added.
But again, if I have to choose ONLY one option, it's definitely option #1.