Vince can 100% make it happen. He's introduced characters like Kim, Nacho, Lalo, Chuck and they were all amazing
If Esposito's idea were taken all the way then we would be seeing the entire cartel and that life unfolding as Gus weaves his way up the ladder as a Don of the cartel. A lot of Juan Bolsa, Hector Salamanca, Lalo, the Cousins I'd imagine. Probably a good deal of Hank's colleagues as well. It would have to be a DEA vs Cartel chess game of sorts to balance it all
I just don't know where Vince would go with it because he likes to showcase a lot of characters and it seems like regular relatable characters have sort of been taken off the table, there would be no normal people in it from the start. There's not many if any at all that Vince Gilligan and Peter Gould could focus on to bring that family element into the story. I guess they could go way deeper into Walt's past and even Jesse's beginnings as a criminal if they truly wanted but it would be a stretch. After all, there is still Walt's brilliance as a chemist while he was creating Grey Matter with Elliot Schwartz and Gretchen Shwartz. I wouldn't mind seeing their plans, chemistry, and relationships play out but I don't have the mind for what could make it super interesting. But it would be a plus because we can see Walt and his family and everyone else while things were promising, actually. When things were better. Can see the communities before they were under the reign of Walter White, and maybe even before Gus started getting serious and crime started to seep into New Mexico
Not sure if there's enough to go by but even if the show were simply just Gustavo Fring and the Cartel that would be enough for me to watch every week