You made me really, really sad right now. Like, you've got those awesome ideas and get really inspired, and then read an article that says horrible things about you if you do things you love and feel good about.
Do you really think you're racist for, for example, including native Americans in your setting?
I see that you're a progressive person and really care about inclusiveness and stuff. But people like you are the most vulnerable when someone tells them "do X or you're not progressive and also a racist".
Cultures get "appropriated" all the time, everywhere on the world. Everyone's culture is "appropriated" by many other cultures, even mine and yours. Do I get offended if one of local myths is misrepresented somewhere abroad? Nope. Are YOU offended when something from your culture is appropriated? 99.9999% you're not. If you want to stay sane, you must understand, that the remaining 0.0001%, despite them being loud on the internet, shouldn't set the standard and tone of the discussion. These are the people who will get offended by everything, mostly.
The point I'm trying to make is that if you're worried if something will offend 0.0001% of people, then maybe consider if that 0.0001% is nuts and you're not a racist fuck.
Somewhere, someone will offended by anything you do. Most people with big followings who "side" with the social justice are eventually attacked by them, despite their best efforts to not offend anyone.
So I just want you to know that you shouldn't want to accomodate crazy people. Sure, some of the things they say is correct and I agree with some of it (but it's the stuff that I agreed with even before I knew about them). Do what you think is right, don't do stuff because you're bullied into "do X or you're racist".
Like, I've checked some of the examples in the link posted by myrthe, and the examples are shit. A game where you play as members of some native tribe is racist genocide? You have black people in your game and they do bad stuff -> oversimplication & racism? Give me a break. It's very easy to find isms everywhere but most of the time they're just so farfetched! Please, be more critical of these kinds of articles.
That being said, good luck and have fun!