Aww yeah...there were so many opportunities for Erik in the future. And that's not just because he's an amazing villain but also because, as you said, he's T'Challa's cousin. It would've been oh-so very amazing to see him. Hell, lotsa people (including my mother) even wanted to see him in the shitty-shit excuse of a movie, Infinity War. They wanted to see him redeemed & fighting alongside his family and his people.

Erik is just...gah, at least we have fanfiction!!!!

And yes about Okoye!!! There's quite a few good words written about how she's an amazing, refreshing example of a paladain, like here and kinda here.

And nyahahahaha! I'm kidding, we are vegetarians...-gigglesnorts- Teeheeeeee!!