This is a list of ideas I have for people who want to build something but need some ideas. Feel free to suggest your own ideas below. Feedback can also go below.
1.Starter Home- You have to create a home that you can buy at the start of the game. This includes anything from one sim's shack to a family's budget mansion.
2. Park- I know it sounds boring but you can make them more complex by changing the landscape, adding plants or extra features or even just simple things like more activities for sims to do.
3. Retirement Home- Create a place for elders to live and then "borrow" some elderly sims from the world and your done.
4. Bar/Club/Lounge- Add some nightlife to your town. You can adjust them to your needs but also add elements that weren't there in the Bridgeport bars/clubs or lounges. You don't even need Late Night really because you can use the bars that came with the base game or other expansions.
5. College- Instead of going to Sim University, you can build a college which allows sims to gain skills even if they have no cash to buy the skill objects.
6. Boarding School- A place where kids and teenagers can study instead of attending the regular school that doesn't boost skills.
7. Dungeon- Troublesome or perfectly innocent sims can be trapped in a dark dungeon for your own entertainment. Also useful as a hideout for criminal sims.
8. Lighthouse- Difficult to build but can be awesome. Just put a light on top of a tall building. Your sims could even live there.
9. Stables- Requires the Pets EP. A place where horses can rest. Could be a place where horses are bred.
10. Shopping Centre/Mall- This is a bit like a general store. All items can be purchased in the same place.
11. Mansion- Try building the most luxurious house.
12. Restaurant/Cafe
13. Castle
14. Gardens
15. Holiday Home- A home specifically for a certain season or just a home with lots of entertainment to offer.
16. Apartment- Communal living.
17. Homeless Shelter- A hotel based building that the public can visit.
18. Forest- A lot filled with trees. Good for pictures, scenes and stories.
19. Resort- Can be built with or without the Island Paradise EP. Townies are able to fill all of their needs there.
20. Fort- Battles can take place here. Probably only useful if you have the Seasons EP.