I agree the timer should be removed. You're paying a subscription, so you're paying to be able to be in a dungeon. You shouldn't need to clear out after 90 minutes to make room for other people. FFXIV should improve its instancing so that people can run the dungeons however long it takes.

I've been in groups of new people that were learning each fight as they went, dying at least a couple times on each. That eats up a lot of time, and players shouldn't be punished for playing, learning the game, and overcoming challenges together.