A writer's narrative perspective (their "voice," or, how they come across to their reader) must be: This is me talking to you.
That's it. Nothing more, nothing less.
It's not: This is me 100 years ago speaking in a "classical" voice.
It's not: Speaking as if from professor to student or from adult to child.
It's not: This is me thinking out loud.
It's not: Look at how clever I am! See what I did with that sentence?
It's just me talking to you.