Where a character's thoughts being expressed is being better than a narrative item is when the character is having an unusual internal dialogue due to concerns about a situation or conflicting ideas on a situation, it shows better as his thoughts than a standard narrative. It also offers more scope to display something about the situation or the character. Here's some examples from my current work in progress, and almost all of the thought segments in what is 21,000 words of a what should be a story of about 50,000 words, or more. There isn't much need for more in what I plan, at this stage, but that may change.
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A few seconds later he's thinking, Was that the drones we shot and blew up? Now he's not so sure of that because of the abort command. He thought it was a test, but the explosion now has him wondering about what did happen.
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While they're moving off to the north-east Will thinks, They look like they belong in a film set in the mid 1800s. Modern Indians all use saddles now and dress in normal work clothes, except when putting on a show for people. I wonder what sighting that group means.
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Stunned at the sight before him, he puts the monocular to his eye and has a very good look around the area. Below is a stream with a hut, a barn, a fenced corral, a group of about twenty-five Indians attacking the hut, with one Indian on a slight rise waving direction with a short spear. It looks just like the Indian attacks on ranchers he's seen in many of the western films, except there are no cameras around, no make-up van, no food van, and no cars of any sort. He studies the scene for a moment, then moves to a better position to fire from.
While taking aim, he thinks, With nothing else to indicate otherwise, I'll assume I'm watching an Indian attack on a rancher and act to end it. This rifle is a twenty-two firing subsonic hollow-points, and intended to help me hunt small animals, but it has the range needed here. First, the guy in charge of the attack, then the three in the stream gully.
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While leading the horses to the hut Will thinks about what he's seen and the gear he just collected, Percussion cap revolvers and rifles along with standard frontier type clothing and behaviour. I wonder if I've been thrown back in time to the mid 1800's somehow?
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In each case the narrative paints the picture and he thinks about what the situation is to add something more to the scene. It's kind of like he's talking to himself, but it's an internal dialogue.
edit for typo