DPS display could easily be solved with a system already in game.

[abzoluut]

Are we talking DF groups here? Would kicking people for low dps even be allowed in DF groups?

Yes it is.

People get kicked all the time. There are numerous threads about them too. When the gm reports back, he basically says it's within the groups right to kick someone for whatever reason they agree on. This can be any reason.

For some reason, a DPS meter would cause havoc to Eorzea. It would be nice if SE would give us the daily number of kicks. You'd be surprised.