MJW is more of a Blade actor. Hard to take him serioously as an actor (do like him though), if they made a retro Luke Cage movie then sure, but i don't see him as a monarch.
A young Hemsworth type is what they should look for, and fill the movie with the actor that should had been BP but are too old.
Chiwetel Ejofor - T'Chaka (in flash backs 40's/50's/60's)
Djimon Honsou - S'yan (modern/90's/80's)
someone like Chadwick Boseman (42, the movie not his age) or Tongayi Chirisa (Crusoe)
We agree with Michael Jai White. Yes, he's ripped, yes, he's a martial artist...but I don't think he's that good of an actor. Certainly not good enough to carry such an important role. Like you, I like the guy. But this isn't Spawn. This is Black Panther: the first (and in my opinion, the most important) Black superhero. Marvel needs to get this right. We've spent page after page in this thread going over why this movie should or should not be made...who will or will not go see it...why it will or will not be a success. All of this debate and conversation tells me that whatever the outcome, IF they are going to do it, then they need to do it right. Every detail, from script to choice of director to locations to casting to marketing needs to be perfect. Yes, that can be said about any film, but we've already gone over (and over and over) why this film would be unique, and somewhat challenging, as opposed to the other MCU releases.
That said, the choice of the lead actor is crucial. And MJW just doesn't come across as the regal T'Challa to me. Not to mention that he is 45. I don't know why that bugs me here, when Mark Ruffalo being 45, RDJ and Don Cheadle being 48 and Jeremy Renner being 42 doesn't (even though I don't like Renner in the role of Hawkeye, his age isn't the reason). I just think a 45 year old MJW is too old for T'Challa (coupled with my other reservations about him).
Where we disagree is on Chiwetel Ejiofor. At 35 (36 in another month or so), I don't think he's too old to play T'Challa.
Since his age appears to be your only reservation, I'm sure we DO agree on everything else: he has the talent (Shakespearean actor), martial arts background and the pedigree (son of Nigerian parents) to make the perfect Black Panther.
But, if they want to go younger, Chadwick Boseman works for me as plan B.