This is like asking "What's the best food to eat?" You need to give some criteria that are important to you. You might want to look at states that don't have an income tax, to start. That can save some money, assuming saving money on taxes is one of your criteria. If you Google for "best US cities" you'll find all kinds of lists with descriptions of various cities and why they're the best. Maybe start there.
>This is like asking "What's the best food to eat?"
The answer is pizza