Our trip a few years back was great.
Flew into vegas - 3 nights at the Bellagio and booked a Grand Canyon trip.
Then drove out through Death Valley and stayed at Furness Creek ( you need to book this place in advance)
Up to San Francisco, which is a great city to spend some time in.
Then down Highway 101 - Monteray, I wasn't impressed by, but the rest was great. This is the Big Sur trip and the scenery is just amazing. Loads of places to stop, we saw seals, eagles, peregrine falcons, ottters, whales, even a dead shark! Also stopped at two vineyards.
Stopped at Santa Monica for 5 nights and visited Hollywood, LA city, Universal studios, Getty museum etc. from there. Santa Monica is just an easier place to be than LA proper. Been there a few times and it's just too full on and false.
Then we drove back to vegas. Stayed one night and flew home to Manchester.
It was a top trip.