IMO the phone is ready to go out of the box, you might never need to change most of the settings to use it (shoutout to samsung for making me spend days removing their bloat on my mom’s phone). Essential notification is the most useful feature that is pretty intuitive to set up. Here’s some stuff I did for a little boost:
I don’t have nothingos beta so AI is not that useful yet, so I installed Netguard to disable internet access for essential space. That turns it into just a screenshot tool to separate important stuff (i take ss of study lectures) from other screenshots, that I sync with my computer with Syncthing. Do note that if you restart your phone with internet on and essential launches before netguard, it will still send your data to nothing servers.
Experiment with your camera settings to find which gives you reasonable quality for the lowest file size, and save it as a default preset. I change to higher quality when taking event videos that easily goes to >200 mb, but the next time I open the app it’s back to the lower quality preset so I don’t burn through my storage.