It's kind of interesting to see that after 16 games this season, City have an xG of ~37, which is identical to what they had after 16 games last season.
Said it before but I don't think he will make 1 bit of difference to them in the league. They'll win most years, they'll have an off year here or there as long as Pep is there, whoever they sign. Haaland doesn't change anything for them in the league. Where Haaland will prove his worth ultimately for them is if they get over the line in the CL, if he can get the goals in the key moments of the biggest cup games. Because Pep has long since mastered league football and will be dominant wherever he goes. Whether the goals are focused in on one individual or spread out evenly, they'll on the whole create a similar amount every year pretty much.