There is no hard cap on them. The population / number of cities requirements just grow with each new one. The actual formula is line 67 if you want to tweak it. No idea. I'll check. That's interesting, never noticed that. Is that a vanilla bug, or was it introduced to RI at some point? Fixed quite a few of vanilla ones already, so I wouldn't be surprised. On one hand you are right; on the other, otherwise with separatism on you'd get a city you have little hope of actually keeping. Scores. If you're more than 25 (flat) but less than 50% ahead, peaking at 35%. Different leaders have different amounts of jealousy too (determined by WorseRankDifferenceAttitudeChange), which determines the maximum negative amount at 35% difference point. I'll have a look.