Its a damned if you do damned if you don't kind of thing.
On one hand if its "less of a Marvel" film we could have really dove deep into some shyt. Probably get a 2hr 30 to 2hr 45 min run time. Let the 3rd act breathe. Let Killmonger's reign last for a bit *Think The Dark Knight Rises with Bane......but a plan and motivation that actually makes some sense*
Its probably less CGI heavy at the end and its on some Game of Thrones Battle of the Basterds type shyt.
On the other hand...Marvel probably is the only one that could have pulled off Wakanda. Without Wakanda on point it doesn't work so you gotta take what you get.
I'll say this....it doesn't NEED the Avengers at all.
Disney is about to milk the hell out of Wakanda because it can be their Lord of the Rings.
they could make a prequel with how Wakanda started with all the tribes earring and the original black panther that united them