At the same time though, we shouldn't perpetuate the practices and notions of the biased casting directors. Far too often, light-skinned actresses have been given precedence over their darker counterparts when opportunities arise where the latter would be a better option than the former. It's an issue of beauty standards and an undervaluation of certain skin tones and facial features that we shouldn't have to play into as a society anymore. And like Black Panther before it, a Vixen movie featuring an actress who embraces traditionally African (particularly Central African) beauty is a strong step in correcting the imbalance and giving underserved communities heroes that reflect what the vast majority of them look like.
If anything, I think that getting a light skinned actress to play Vixen would hurt the movie because I'd imagine a lot of WOC would feel it was a missed opportunity to show a dark skinned woman. Part of the reason BP was such a success among audiences was that its women weren't beholden to white beauty standards that devalue black women and their attributes. A Vixen movie featuring a woman whose a few shades and a nose job away from looking like Emma Watson isn't going to go over well in the wake of characters like Nakia and Okoye.