Yeah, that's why I'm ending up just wiping them out. In my current game as Scynthia I had 2-3 joint wars on me in the early game. A common enemy in all of them was Arabia and so with the third surprise war from them, I decided to cleanse them from my northern borders. Then the much larger Brazil decided to go for a round two and I wiped them out as well. Though during the course of the Brazilian war I had some musket-men rebellions because this war dragged on for so long (I refused peace like four times) and I was really low on cash. After a little bit, Sumeria decided to try me out with their capital on the border facing me. I didn't wipe them out since they had some sub-five city on some island off Pangaea.
Now I manage 20+ cities which is a mess. I might just raze everything else if Norway or Britain decides to fight me. I gotta channel the steppe people somehow. I kind of wish we had Genghis Khan but I suppose Thmyris/Scynthia replaces him.