(Another thing to filed under: Never Going To Happen)

... more or less just what the title says; make every job a DPS that has a "stance" that is either Tank or Heal that when triggered will lower their damage to Tank/Heal level and change their secondary rotation to either a set of defense buffs or heals accordingly.

Healer OR Defender, _NOT_ Healer AND Defender.

Optionally: I could imagine having a mechanic where while playing solo your stance is more generic, like 80/20 in favor of DPS, but in a party you would have the enhancement "Teamwork" and it would be a more drastic shift as you focus more at working as a team. Also, your role Icon would change while in a party to reflect your "stance"... that way it is easier to visually coordinate.

I don't know... just a wild idea. I'll go climb on my pile of firewood now and wait to be flamed.