Are you staying at the Disneyland hotel? The one at the entrance of the park?
If so, you can book princess meets on the Disneyland app at your hotel. As soon as you have done the first, you can book the next.
When are you visiting? If it's soon then it might be too late, but if you have time, being a Disney hotel guest you can book restaurants a year in advance of your visit. So I suggest you try and book some restaurants if you want to eat at a Disney restaurant or do character dining.
Use magic hour for that quieter hour in the park.
The shows are great. Especially the Lion king show. If you have time, try and see a show.
Currently there is a special musical parade on 3/4 times a day called Splash of colours. Try and see at least one and aim to get a good spot about 30 mins before near the castle.
Some rides are quiet in the evenings so don't bother queuing for over an hour for rides that go down to 5 min wait in the evening. These are rides such as Small world, pirates of Caribbean, star tour.
Have fun 😊