Didn't want to start a new thread. But it seems like the real question is if all classes were available what would the make up be? Most people seem to agree that any class played right can be valuable. So here is mine.
Cleric, no brainer i think = Healer
Paladin. Bias here = Tank. Stuns are good off of pull. I get aggro and by the time a mob is on me its dotted, de-spelled and slowed.
Shaman = Slower. Nice buffs. Dots and can take over heals for a bit and nice pet too.
Bard = Puller. Never seen a good Bard bring anything but singles.
Rogue = DPS. IMO the best DPS is game. Spells can be resisted. And require mana. Melee goes on forever.
Mage = DPS. Nice damage. Solid Pet.
Why i did not choose.
Necro. In power groups. Dots do not run corse. FD necros on bad pulls can rez. But i never make a group thinking about a wipe.
Wizard. If they nuke to fast you hear OoM. Without someone feeding them mana over a long grind it will happen.
Berzerker. Close with rogue. But wanted large magic blasts for last DPS and choose mage.
Druid. Very nice. But with nuker mage and back up healer shaman there utilty is third on the list.
Monk. Good monks make great pullers. And good DPS. Just not enough to overide Bard or Rogue.
Ranger. Again good pullers and good DPS. Just not number one.
Enchanter. Mezzes are nice. Mind buffs rule. Pets are good. But just no room. Bard should have singles, eliminates mezz, three healers(cleric, sham and pal) should not need healing mana. Bard song helps replace mana too.
Shadow Knight. Make fine tanks. Good at holding aggro. But just no room.
Warrior. Great tanks. But little utilty. In raid settings. They are best tanks. But in groups i like pallies better.
Beastlord. I like Beastlords. Would toss them in very easily. Great pet. Average buffs and good slows. Would be seventh choice.