I'm hoping he's not the main villain. I want to see him as a winter soldier type character with Moses magnum being the puppet master
That'd be a weird reversal for me. Not that Moses Magnum can't be a led villain, but he seems inherently less mastermind-y than Klaw.
How many Black Panther movies do you guys envision? A trilogy? Or more like one solo film, then just a key Avenger?
I envision two specifically, but I'd like trilogy.
The first one is the "War for Vibranium," where we see what makes T'Challa Black Panther and pretty much just explore his abilities and motivations. This would naturally have Klaw as a main villain. It can feature M'Baka or Moses Magnum as a secondary villain in alliance with Klaw, or you can use a mercenary crew not unlike in Who Is the Black Panther storyline, which is a good storyline to adapt, minus a little slang and political 'take thats.' You also may want to consider having some heroes be the secondary "villains" and having someone like Hawkeye or even Hulk playing the role the Fantastic Four played in Black Panther's first appearance, an idea/scene which has been adapted in Earth's Mightiest Heroes and Ultimate Avengers 2 cartoons where Black Panther whoops our heroes. In fact, other heroes jobbing for him was one of the biggest innovations Black Panther had going for him. That needs to be a big part of his first appearance. It is necessary for him to have that "sixth Ranger" type of appeal. After winning this war T'Challa should be established as an all around badarse superhero and master of Vibranium and it's applications.
The second is the "War for Wakanda," where we sort of get gritty with what Wakanda is and is not and we have our messiest political storyline. This is where combat mastermind and archnemesis Eric Killmonger comes in to play. The secondary villains are largely unimportant. Essentially, you are adapting the groundbreaking Rage of the Black Panther storyline that kind of invented the long-form comic book storytelling we enjoy today. This is where we strip T'Challa down a bit and force him to confront the darkest reflection of himself in Killmonger. You can throw in Wakandan mutates, but if he's making one of his famous trips to New York here, you open up room for everyone from Red Ghost to Stilt Man. If you throw in shades of Doomwar, you could use Count Nefaria to stand in for Dr. Doom and have him in a third place with Killmonger playing Shuri's role as a temp ruler and warmonger.
The third film can go a number of directions, but at it's heart it really should be the the "War for the Black Panther" where T'Challa has to fight for his very core essence. The villain here could be his brother White Wolf, or Achebe, or both.
As suggested below, while Wakanda would always be an important location in the story, there's no reason Wakanda needs to have the majority of the screen time in any of the films.
Historically, what is Black Panther's role in The Avengers?
Is he more of a leader, or just a member of the team, or an occasional member, a la Aquaman?
He was kind of a sixth ranger, sort of on the edges, and coming through in the clutch. In recent times, with the New Avengers, which I suspect the MCU AVengers might be more like post A3, I think he's kind of a board chairman. Not so much a leader, but a facilitator in a group of leaders.
Hope if they do a couple of sequels they keep him mostly in Africa, with only short trips to US or America. Being a leader you can make it a bit more political. Talking to the UN, other leaders etc... haven him be a cross between Nelson Mandela and James Bond.
Have him stop wars, assassinations etc...
Not Wakkanda. But Africa. The continent is so vast. Bigger than the US, China and Europe put together. Bring in some Indiana Jones elements/Tarzan elements etc... Will give BP a unique flavour in the Marvel universe.
That's actually pretty inspired. I'd really love them to get into the diversity of Africa. Endless Savannas, Lost Kingdoms, bustling metropolises, brutal dictatorships, third world marketplaces, mountain vistas, crowded streets, hopless deserts. Don't think they will, but it'd be pretty fracking awesome. Also action-political has potential. Sort of a throwback to the warrior-kings of ancient times, both figuratively and thematically, and literally I think, but also literarily. But I digress. Aggressive negotiations, played straight, for the win.