I have lived in San Francisco and now live in Chicago and run my own startup- but NorCal is definitely the best place on Earth to be. There are other great places- but IMO the best is still Northern California
Everything depends on your personal situation. If you are launching a startup, LAUNCH IT. You don't need to be in SF.
If you want to live where the center of the startup universe is, if you want to not be able to swing a dead cat around your head without hitting another entrepreneur, if you like it 60-65 degrees almost every day of the year, SF is the place for you.
You don't NEED to be in SF to launch a startup unless your service/product is narrowly defined as SF residents using it. Plenty of startups move to the Bay Area when they need funding- but...you can always visit and check it out yourself.
I'd say, launch your startup now. That is key- forward momentum.