PlanetsCentral

Well, I don't like the idea that some bored players or some with no chance to win anymore will decide that the game is over. So I say no here.

Keeping 150 planets for 10 consecutive turns is way better winning/ending condition. You know exactly what you need to do in order to win and others know exactly what they need to do to stop you. Just put this condition in turn 90 so the fastest win could be achieved turn 100 and everything is fine (at least for me).