Vote-kick only requires a simple majority?

[Tsukino]

They will be punished later for kicking you without one of the listed reasons: AFK, Offline, Harassment or Cheating.
and: * 4 hours must elapse since your last vote dismiss before you can initiate another.

1. This remains to be seen. Right now there's not even a way to report people found on other servers, so how are four people going to be proven to be abusing the function? SE also doesn't even seem to have enough resources to ban obvious RMT who have been repeatedly reported, so where are they going to find the time to investigate this?

2. Only one person has to initiate. The cooldown doesn't mean a lot as long as four people are willing to vote to kick them anyway - one of them probably has the kick available.

[Curagaja]

Right now there's not even a way to report people found on other servers

You can report players from other servers. When you file the report on a player from another server you will need to include which dungeon the event occurred in, the name of the player you want to report, the server of the player you want to report, and usually the time period. The server can be found by looking up the player on lodestone, comparing gear, title, jobs, etc. with the player you are trying to report.