What do you think about my route Northern to Southern CA?
 

1 Arrive at San Francisco International Airport. Secure rental hire (arranged independently) and drive to hotel. Overnight at Four Seasons San Francisco.
2 Morning at leisure. Afternoon Alcatraz Island Tour. Overnight at Four Seasons San Francisco.
3 Full Day Tour of San Francisco to include Golden Gate Bridge, Disney Museum, Legion of Honor, de Young Museum, and Golden Gate Park. Overnight at Four Seasons San Francisco.
4 Full Day Tour of San Francisco to include MOMA, Exploratorium, Fisherman’s Wharf and Sea Lions, Chinatown, and additional sightseeing stops as requested. Overnight at Four Seasons San Francisco.
5 Morning at leisure. Drive 3 hours to Pebble Beach via Highway One.Stop in Half Moon Bay for lunch. Continue to Pebble Beach. Overnight at Casa Palmero.
6 Morning tour of Point Lobos State Park (flat short walk that can be customized to mum and dad’s needs).
Afternoon Monterey Bay Aquarium Tour. Drive to Big Sur. Overnight Ventana Inn or Post Ranch Inn.
7 Drive 4 hours to Santa Barbara. Stop en route for Hearst Castle Tour. Overnight at Santa Barbara at Rosewood Miramar Beach Montecito or Belmond El Encanto.
8 Morning Tour of Old Mission Santa Barbara. Afternoon free to enjoy beach. Overnight at Santa Barbara at Rosewood Miramar Beach Montecito or Belmond El Encanto.
9 Drive 2 hours to Los Angeles. Stop en route for a tour of the Regan Presidential Library and Getty Villa. Overnight at Beverly Hills Hotel.
10 Full Day Tour of Los Angeles including Norton Simon Museum and Star Homes. Overnight at Beverly Hills Hotel.
11 Full Day at Universal Studios – VIP Tour. Overnight at Beverly Hills Hotel.
12 Foodie Tour of the Original Farmer’s Market or Warner Bros. Studio Tour. Drive 1 hour to Anaheim. Overnight at Disney's Grand Californian Hotel & Spa (Club Level)
13 Full Day Admission to Disneyland Resort’s California Adventure Park. Overnight at Disney's Grand Californian Hotel & Spa (Club Level)
14 Full Day Admission to Disneyland Resort’s Disneyland Park. Overnight at Disney's Grand Californian Hotel & Spa (Club Level)
15 Drive 40 minutes to Dana Point for a Ferry transfer to Catalina Island. Day on own on Catalina Island.Return Ferry. Overnight at Monarch Beach Resort or Montage Laguna Beach.
16 Morning at leisure. Drive 1.5 hours to San Diego. Overnight at Fairmont Grand Del Mar.
17 Half Day San Diego City Tour. Overnight at Fairmont Grand Del Mar.
18 Full Day at the San Diego Zoo – VIP Tour. Overnight at Fairmont Grand Del Mar.
19 Drive to San Diego Airport. Return rental car. Fly to Las Vegas, NV (airfare arranged independently). Private transfer to hotel. Overnight at MG Grand Skylofts.
20 Half Day Tour of Hoover Dam. Overnight at MG Grand Skylofts.
21 Free Day on own to relax or explore Shark Aquarium, Bellagio Gardens, etc. Overnight at MG Grand Skylofts.
22 Private transfer to airport. Depart Nevada.

Not sure about about the LA and Vegas portions of your trip, you might want ask in those dedicated forums. I'd suggest not renting a car until the day you leave to Pebble Beach, as you don't need a car in SF and you will be charged parking. I'd take a taxi or shared ride from SFO to the Four Seasons.

You might have too much on your list for Days 3-4 in SF. It depends on how much stamina you/your fellow travelers have, how long you wish to spend at each attraction, and how willing you are to drop an item from the list if you fall behind schedule. Be flexible, plan around when attraction close for the day (it's no good if you've got stamina until 9pm when everything closes at 5), and allow for driving time between SF locations to take 2-3x as long as it seems it should.

For the San Francisco portion, there is absolutely no reason to have a hire car. You will spend most of your time looking for parking, which will be incredibly expensive. Plus renting from the airport incurs large additional taxes/fees. Use Uber/Lyft to get around town.

Pick a car up from a downtown agency on your Day 5 morning on your way out of town. Most of the major agencies have downtown locations.

San Diego Zoo leaves a lot to be desired. Half a day is plenty and unless you are a huge fan of zoos, just skip it.
I would including Liberty Station. close to the airport. some nice shops and great places to eat.
Instead of the Zoo I would spend a few hours walking around Balboa Park.
agree with everybody NOT to rent a car while in SF. Most hotels will charge $ 60+ a night to garage the car + you don't want to drive in SF.

You don't say what time of year you are coming. It might make a difference in the advice.

Be sure to book online well in advance for the Hearst Castle tour. Spots go fast.

We have changed the route to 22-27th at St Regis in SFO
28-4th at Monterey, Pebble Beach at Big Sur Hotel
should we be in San Fran on the 4th of July
and besides Saison what should we do

You can wander the Original Farmers market and the acclaimed outdoor shopping mall "The Grove" without taking a tour. If you are really into food, check out a great local restaurant (perhaps have your hotel book something in advance of your arrival to be sure you get into one of the many new and great places.

I think you have way too many places ,
Pick 10 things you do not want to miss , and work around them,

​​​​​Traffic in the Bay area and Los Angeles will take a good part of your time ....

Day 9 is a bit ambitious, make sure you have Getty Villa booked well in advance because they have limited access IIRC. Have a backup plan. Getty Museum on the 405 is more along the route you'll take to your eventual overnight destination at the Beverly Hills Hotel.
Day 12 "drive 1 hour to Anaheim" bwahahahaha
Day 13 and 14 - You will be at Disneyland Resort in the middle of summer vacation season and Star Wars Land is set to open May 31st. Be ready for crowds, will need reservation for Star Wars Land, may be automatic since you're staying on property but you should confirm. I'd skip Catalina island on Day 15 and use that to catch whatever you didn't make it to at the two parks.

15. Overnight at Monarch Beach Resort or Montage Laguna Beach.
Monarch Beach Resort may not be as fine a hotel as in previous ownership. Pacific Coast Highway (PCH) is between hotel and beach.
Montage Laguna Beach does not have PCH distracting ambiance of ocean setting. Montage standards remain high. The Laguna Beach environment has little impact on either hotel.

Yeah, unless you have young kids, I would dump Disney in favor of more time in the Laguna area or Sand Diego.
Traffic in LA is horrendous. We spend 2+ hours in the middle of the day getting from Santa Monica to downtown LA.