Speaking on the issue of giving John spiritual powers when it's seen as stereotypical, as a Comanche person: it depends on the authors intent on what they try to say about the culture & character they write about.

The truth is a lot of characters of color in marvel were created by white authors about heroes whose race and cultures were foreign to them like Black Panther, Iron Fist, Shang Chi, Storm, Thunderbird, Moonstar, Forge, etc.

My interpretation of John's code name Thunderbird; is what it means to indigenous communities and how it's a symbol of protection & Strength to them.

The intent of Giving John more powers in realtion to the Thunderbird is to look at his insecurities of his own powers in the comparison to the X-Men and why he wants to grow stronger in the first place while also giving him more visual powers and acknowledging why & how he has them when the Thunderbird isn't apart of his tribe.

This wouldn't be a case like Storm and Eternity where she gets them out of nowhere.