Welcome to my perfumed garden

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When I read italics, I "hear" a change in voice -- emphasis, or thoughts, or dream (vision) sequence, or over the telephone, or another language, or sentinel hearing.

:::StarWatcher stares at the list::: Whew! Didn't realize it was so much; impressive what a crooked letter can do. *g*

But first person doesn't justify a "change" in voice -- it's still just "direct" storytelling. And, as you say, reading longer than a short scene in italics can get tiring for the eyes.

I'm wondering whether it's not better to just leave it all the same and let the narrative passages speak for themselves?

That's the solution I'd go with. With a scene break to let us know that 'something' has shifted, the reader should recognize first person -- and who's 'speaking' -- before the first paragraph has finished.

The K.I.S.S. solution -- Keep It Simple, Stupid -- is usually best.
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