What is the devaluation? Tchalla shouldn't be able to negotiate strife between species he barely knows. Maybe eight years of exposure to them while at the same time be unaware that slavery was happening under his nose. Set up like that, anyone from Wakanda prime shouldn't be leading the Empire. Its grown beyond their capabilities and experience.
The devaluation is not having T'Challa the Black Panther firing on all cylinders just to tell a tale about a supporting character. You see, the trick is T'Challa is a polymath and a master of strategy and tactics and as such is a quick study. He should be seen successfully negotiating the strife between species he barely knows. Why because that is what makes him more the hero, the super hero we want to read about. Priest often demonstrated T'Challa's political savvy. Remember this.

I agree that the set up is important and it requires a writer studied in geopolitics (on a cursory level), full of enthusiasm and imagination with a creative flare to tell the story in a unique way tailored to the Black Panther. Wakanda Prime should most certainly be leading the Intergalactic Empire of Wakanda with T'Challa as emperor. Telling the story of how T'Challa deals with and learns to govern an empire spanning five galaxies offers a plethora of original story potential. T'Challa is and has always been, back to his inception, a leader and a king.
Even the mutant known as Angel understood this back in the eighties.

Dare I say he was cloaking back then.
Wakanda is supposed to be the most advanced nation on earth and it is past time to show it. No more stories, especially in his own comic, of faux revolutions and T'Challa naval gazing while dreaming of being an Avenger.
For years it was argued that T'Challa is Marvels Batman, no he is not and never was; the Black Panther is equal to Captain America as if that was some kind of accomplishment; put him on the Avengers, let him work his way up the ranks til one day we can see him as a leader. The Black Panther is bristling with original story potential.
The bolded is how we end up with unfans who say we only want Tchalla seen as 'great, great, great' and then we have to correct them showing them examples of him going though hardships. This empire thing is one of those examples. The Isekai anime trope of the human being dropped into a new world and immediately taking control is fun, but that usually happens because of how weak the world he gets dropped into is. I don't like the concept of the empire, but I don't want it to be some weak toy that Tchalla can just easily fix because he is so great.
T'Challa is great, that's why he is a successful superhero franchise. Those unfans you speak don't even read the BP comics so why should fans and enthusiasts have to show and prove anything to them? Let's not focus on unfans and point our attention to T'Challa the Black Panther reaching his potential.
Coates littered the Black Panther with tropes... cosmic slavery, rape camps in trees and a milquetoast "black" male lead. At least with the empire we get to go big and tell stories that span the cosmos or is it we have to keep vacillating between street level activities and romping with the Avengers?
The reason Coates story sucked was because he was putting Tchalla into situations that were well below his abilities. The empire storyline should take at least five years of storytelling of victories and losses before it comes easy to him.
Not necessarily easy as much as worthy of his mantle.