Honestly, all of this makes me want to go back to that one scene I thought was finished and read it like I’m prepping it for an audience of ten strangers with no reason to lie to me. If it stumbles, I’d rather know now than after it’s in print.
choose a scene of interest and just record yourself narrating it. then watch/listen to it. see where it appears like you need to force yourself to emphasis things, where the word plainly spoken does not convey the importance of the story, but your brain knows its of importance. where you need to use your vocals to push the words further..(like a subtle nudge/wink to the audience that they need to be aware a detail) then adjust those words to be pushy by themselves by changing the words
reciting the story to yourself vocally not only prepares you for any speaking engagements but also lets you hear the story in a different format(instead of written paper) and allows you to hear if its even good enough for a audiobook.. because lets face it not many people have time to sit still and read, they prefer to listen to audiobooks while at the gym or work or doing home chores. so it can help prepare the story for audiobook format
if your book was to be made into audiobook format, and a publisher hired a narrator. your story should be readable that a narrater that does not have your vision in mind can see where the things of emphasis are, via the word play you use. so without pre-coaching a narrator about which parts to emphasis with vocal pitches/emotion/tone. try to use specific words that convey its importance to the story plot