Not sure this issue will ever be addressed to the satisfaction of the gentlemen who left this post. Because, there will always be one 'best' way to do something and it is up to the players to learn how to manage their skills/abilities to fit the situation. That being said, there are some things the dev. team can take to promote a balanced approach. Assuming they know the 'best' approach in development (1 tank, ranged dps, and healers), they can make changes such as make the monster weak to axe attacks, or stunned by lancer attacks (trammel), etc to promote innovative approaches.

P.S. Anyone remember that JP LS that did a full Monk 'Divine Might' fight? Sure the video is still out there.