Tangent aside, I think regarding alliances it would be better to have 2/3 majority rather than bare majority just because there are far more people involved. I think it's a compromise between the people who dislike being forced to restart a dungeon because or trolls or quitters or what have you, and the people arguing a simple majority is enough. Plus, three full parties, 2/3 is majority among parties, etc.

As for the vote spamming, I don't understand why there isn't a restriction on it to begin with. Once every 4h (I think that's the timer for vote kick?) is obviously too long but even once every 10 minutes to give a group some time to fail before calling it quits seems fair. Any shorter and it may continue to be obnoxious, but any longer and you deny people the opportunity to re-evaluate the situation.