Speed runs aren't representative of class or job viability. 4-mans can be cleared by any set up within the tank/healer/2DPS spectrum. 8-mans encourage balanced parties to get the most bang for your buck. I'd say the approach the game has taken to that has done well enough.
The game is as bland as you let it get, as uniqueness will always be trumped by functionality and balance at the end of the day. If you get bored because you have no one to purposely exclude from content, then I think you have bigger problems than whether the game is bland or not.
