Well, that's why I said POSSIBLY a BO4 cause I know, nothing has been confirmed yet.
But I agree with you on the boots of the ground part of it. But honestly, I think they should go back to where BO2 left off. I know there's alot of endings, but they should go back to the canon ending, explore what happened, like if Menendez escaped, and what's the future for Mason, cause he's alone, Harper's dead, Salazar might be plotting revenge, Woods might be on his death bed, who knows?
I love the BO2 storyline so much, that what I just said, they should conclude it in BO4, cause there are still unanswered questions there.
As for the zombies, hmm, Idk how that would go. What would be your next take on the zombies for BO4? ^^