From people afk'ing in dungeons, to people refusing to help kill trash, to severely undergeared players, we need the ability to remove players from an instance to better the playing experience for others. A voting system would be even better.

Granted, this could be a double-edged sword as there are a ton of douche bags out there (mostly thanks to the porting of ARR to the PS3) who would abuse this system just to grief other players. And I'm willing to deal with this just as long as the rest of us can use it for justifiable reasons.

Why isn't this already implemented is beyond me.

Also, the ability to add players in Hard Mode instances is needed, as well.

Actually, the whole Duty Finder needs a make over. To start, the DF should have filters that add players to groups by their selected experience option. Maybe have a gear ilvl requirement to enter particular dungeons. So many things...but the "remove player" function should be priority!