Quick update. Just finished this game on Emperor as Shoshone, winning diplomatically and snowballing after getting a couple of vassals. There was decent gap from my #1 on scoreboard to my vassal Genghis' #2. Even as I steamrolled the rest of the map he never requested liberation even though he could've (he turned out to have a much larger army and even more cities than I had after swallowing Russia!), and also stayed a vassal even when the entire world started hating me (Genghis included) from snowballing. I guess it's a good thing I targeted him and vassalized him early and quick!