Answers 1:
*Chez Panisse in Berkeley. Although this place doesn't hold a Michelin star, Alice Waters is a well-known chef, and the food is locally sourced and seasonal. It is a 'MUST' go restaurant. The place has a rustic and warm feeling, not 'stuffy' at all. The food is just amazing.
https://www.chezpanisse.com/

*Quince (3 stars) in the North Beach area. (close to Transamerica (triangle) building.) I've eaten dinner once, but often eat lunch in the outdoor (parklet) area. Naturally, it feels a bit more formal for dinner, but you can dine casually during lunch. Also, SF restaurants (even some of these Michelin-starred restaurants, people dress rather casually. Even in those more formal places, a tie is not required.
https://www.quincerestaurant.com/

*The Progress https://theprogress-sf.com/ Although it only has 1 star, each dish is very unique and I always recommend my friends to try it at least once. This place can get noisy.

*Saison https://saisonsf.com/about/ I've been here once. It's an open kitchen and the food is great, but I don't really care for its decor.

*If you are unable to book French Laundry, you can try Bouchon https://thomaskeller.com/bouchonyountville/ It is owned by Thomas Keller (French Laundry)

Answer 2:
The most economical way is to use Uber. (approx $120/one way)
If you want a private transfer, it can cost around $700/round trip plus tip
It'll take about 1.5 hrs if the traffic is reasonable.

Answer 3:
It really depends on where you'll be going for the Michelin star experience. But you can always go to the Ferry Building and find 'good eats' there. Not all places have 'eat-in,' but you can grab some food and go outside, sit on a bench while seeing the Bay Bridge and ferries go by.

Answer 4:
Sausalito is tiny, so it doesn't take much to explore. Just walk along the water, and do some souvenir shopping. Le Garage (Marina View) https://legaragesausalito.com I haven't found 'the one' in Sausalito.

Hi, there seems to be a limit on how many words I can type, so my answer may sound short. (sorry)

Golden Gate Bridge: the view from the Northside of the bridge is nice. Otherwise, city of SF is very walkable and public transportation (bus, underground, cable car)

Another perfect location to see GGB is from Marina district (Crissy Field.) While you are there, you can walk along the water to the foot of the previous bridge. If you want to see the bridge from the West (Pacific Ocean) into the Bay, you can also visit Legends of Honor.

- We'd like to try a driverless taxi (Waymo). I don't trust it so I've never taken it.

First, I'd walk to the Ferry Building. If you walk to Market St. (few blocks from Union Square) and head East, it's about 15 - 20 manan walk. If you go there on Saturday morning (9 am - 2 pm), there is an outdoor farmer's market. You can grab food at the Ferry Building as there are many eateries and shops, while looking over the Bay Bridge. If you leave the hotel around 2 pm, you can spend at least 2 hours at the Ferry Building if not more. Then you can walk towards Fisherman's Wharf (15 min walk along the water.) After walking around there, you can hop on the HYDE Cable Car back to Union Square.

Yosemite is at least 4-hr drive each way, so unless you plan on staying near by, I don't recommend going there during this trip. Instead, you can go to the Golden Gatee Park and visit: California Academy of Science, De Young Museum, and they even have a Japanese garden. In town, there is MoMA within a walking distance from Union Square.