I'm kinda new to the game but I realized that I'm more into roleplaying and playing open-ended games instead of completing scenarios or goals...
Mine are:
"Stock Market Genius" - I like to try and figure out in the first year of the game which company/stock will perform the best after 15 years, to do so I analyze financial statements, operating investments, CEO expertise..
"Media Baron" - To try and take control of media firms within a city or multiple cities before AI, profit from them and also control how and how much AI will advertise its own products.
"Semi products Supplier" - This one I did when I realised how many products in the game are made from plastic, steel and electronic components. If you take control of the supply of these ones, you can have AI in your hands.
These are some of the roleplaying ideas I tried to put into practice. What are yours ?