This is a question everyone wants to know the answer to.
My three suggestions are:
The Sims 3: On the Water
This is my first suggestion because I believe The Sims Series should have boats.
New Neighbourhood Possible Names:
The idea of this neighbourhood is to make a suitable location for what I want.
New Jobs Possibilities:
Fisherman - Skills: Fishing, Handiness
Scuba Diver - Skills: Athletic
Life Guard - Skills: Athletic, Surfing
New Skills Possibilities:
New Traits Possibilities:
Your Sim is the peak of cool. They can't put a foot wrong.
Your Sim love water. They have to swim all the time, they love surfing. They even have to live near the ocean.
Sims with this trait are almost certainly going to go well in the Scuba Diver career, and will be most sims at holding their breath.
New Lot Types Possibilities
New Things you could do Possibilities:
Swim in the ocean
Travel overseas by boat
Swap from one neighbourhood to another
Own two homes in the one neighbourhood i.e. One as the house you live in and one as a renovater/child's future home
New Objects Possibilities:
Other Boat/Surf related objects
Correct what you think is wrong or how you can improve it.
The other two will be in two other blog posts. They are The Sims 3: Education and The Sims 3: Air Travel