Do people like the unique improvements you get from city states?
Ive played around with the giant heads, monestary and alcazar a fair bit - they have terrible yields, although the alcazar is not bad (culture). They’re kinda handy if you have some flat tiles that have special yields (eg because of a natural wonder).
They are lots of fun though, particularly where your civ doesnt have a unique improvement. I wish the monestary and alcazar gave a little housing or something, or they maybe all had some adjacency bonuses. But either way, theyre good fun.