I'm on a standard map size, it matters.6 cities is considered wide? Around 6 or 7 core ones and sometimes 1 or 2 overseas has been my go to for a tall tradition game. Does map size matter on that?
No, 6 cities isn't wide, but my point is that with 6 cities, I have more than 50 spare happiness, so I could settle 4 new cities that each had 10 unhappiness, and I'd still be happy. Unless you go really, really wide (which probably means warmongering), happiness is pretty easy by about the medieval era.