California can be awesome but everything is very expensive (lived there for 50 years). The state parks are almost all $35 a night and they only discount geezers $2. Gas is the highest in the lower 48 and the cost of everything else, like groceries is much higher than here in Arizona (not sure about the rest of the country).
You will encounter large crowds just about everywhere you travel throughout the state. Weekends, particularly holiday weekends, are insane. Best to hunker down somewhere and stay off the roads. Now if you can deal with all of that it is hard to imagine a state with more to see and do. I'll never live there again but we do visit often.
As always..... Opinions and YMMV. :C