Hello,
I'd like to suggest some ideas for expansions:
1. Something like "open for business" from the sims 2, just make it a bit difficult with more options.
2. More carriers, different sports can be a carrier choice
3. You can put martial arts, also inside of a business -martial arts school as business.
4. More places to travel to, as within the city and expanded
5. Pets definitely
6. You can try making the game more engaging with jobs
The game is great, btw.
As I come up with more ideas, I'll email them.