Yes that is correct. If you are using a different light setting between normal lights and night lights then make sure you also select If lights are ON, adjust the lights when crossing over in Night Light Control.
Yes that is correct. I have a 
Zone Presence of People & Devices blueprint. If you set this up using the Presence Helper option, it will create a toggle helper for you. You can then use that toggle helper in the State Control option.
This way, you only need one presence automation that you can manage in a single place, and then reuse it across multiple automations. It also includes built-in delays, so when someone enters the zone, the lights can turn on immediately, but when they leave, a delay can be applied if you’d like. This acts as a nice buffer too, so your lights won’t turn off if your device briefly goes away and then returns to home within the delay time.
This zone presence of people & devices can also turn light ON and OFF in the custom actions if you prefer to use that. I also have a 
Smart Light - Entity - Sun Elevation - Ambient & Time Triggers blueprint you can look at.
There are many ways to do it but you will have to work out what is best for you.
Blacky 