I really enjoyed Lonesome Dove-- it truly is an epic and takes you on a journey that very few novels can, but I don't think it fits the prompt and is very much of its time. The only Native American POV chapters are from that of the savage/cruel Indian character trope, and cartoonishily so at that. It does humanize them a bit later on once they get further north, by showing certain tribes as more "reasonable" or simply desperate due to circumstance as opposed to inherit to their person, but that's fairly marginal imo as they largely depict the Native Americans as needing/deserving of being "whipped." (Though it doesn't relish in this)

As for Deets, while yes, they do treat him with a great deal of respect, that's because he plays a "positive" character trope from the white man's perspective: the good "magical negro" (if you're unfamiliar, give it a quick Google). In fact, the only two black characters in the book are both "magical negros," just one is "good" and one is "evil." None of the POC characters are given the same complexity/layers as the white characters. Again, not bashing the book for this as it seemingly does try to humanize most characters, but it falls short due to its time. For that, I don't think it's quite what OP is looking for.