What I’d like, I think, is something that really zooms in on a specific culture and shows it in a level of detail that doesn’t come across in-game. My first instinct is Forsaken, but that may just be because they’re the ones who need it most right now, given how they’re being portrayed. A series that takes place entirely in, say, Ironforge would be equally interesting. Inter-clan intrigue, gnomish hijinks, crazy Archaeologists studying the bones of dead gods.
What it would actually be, imo, is a Second War chronicle that focuses heavily on the human kingdoms - trying to pick people up as Game of Thrones is winding down.