He did use darker makeup on certain occasions though. I always felt like he was trying to get his color back with makeup, until he couldn't anymore.
Examples being:- Liberian Girl video, Come Together video, Annie Leibovitz photoshoots, his visit to Japan, John Branca's wedding. He was trying his best to revert back to his natural color with caked on makeup.
Sorry for the late reply, when I say to use black make up, I talk about to be full black and just for music video, imho he shouldn't have done these 2 years concert, he hated that, it would have been easier to use these make up for 3/4 music video and a live show, it was not wise from him and from CBS to let him appear like that without any explanation for 5 years.
For a missing opportunity, I have found two, first the duet Batman soundtrack with Prince, I think it was his best chance to beat the sales of Thriller (from wiki):
"In a 2010
Rolling Stone interview, Prince revealed that the project was initially supposed to be a collaboration between himself and
Michael Jackson: "Did you know that the album was supposed to be a duet between Michael Jackson and me? He as Batman, me as the
Joker?" Prince would have sung
funk songs for the villains, while Michael Jackson would have sung
ballads for the heroes. This never came to fruition as Jackson was busy with his
Bad World Tour and already signed with
Epic Records (the label he had been with since 1975), while the film was a
Warner Bros. production."
The second one was another movie project, according Jermaine book he have tried to call Michael in early 90's, if I remember it was before the tv show about his family, to make an tv show about the Nubian Egyptian dynasty, that would have been awesome, specially the soundtrack.