5th wheels.
I'm of the opinion that the Bard makes a good 6th wheel.
Human works best, but others work as well.
Group of 5 Optimization at 10th level:
Straight Wizard 10,
Straight Cleric 10,
Fighter 2, Barbarian 1, Rogue 7. Then Straight Rogue from here until level 20, where you pick up a level of Ranger before you go epic.
Straight Druid 10
Fighter 5, Barbarian 2, Rogue 3. Then Straight Fighter from here.
The Cleric, Wizard and Druid would be built as Casters, not Tank Cleric, Gish, or Wildshaping combat Druid.
The Cleric can be a little more offensive in his spell selection, and could always engage with Righteous Might/Divine Power/Divine Favor, but will probably wait until Quicken Spell makes sense. This type of build probably has a lower Strength, and Constitution then normal for a Cleric, while maxing out Wisdom, and keeping Charisma high for turning, and Dex and Int at respectable levels for AC, initiative, and skills points. Eschewing weapon feats for Spell Penetration and Greater Spell Penetration, is also a probable direction.
The Druid should focus on Summonning multiple creatures: Spell Focus Conjuration, Augment Summoning, Natural Spell, and Spell Penetration, are probably the starting feats, with Greater Spell Penetration, and Extend Spell to follow. Track also makes sense. After a few more levels, the Druid will probably be more comfortable WildShaping into Large creatures and wading into combat. The Druid has probably punted most of the physical stats, and along with a maxed out Wisdom, has a high intelligence so he can max out his skills. If Human, he can come close to maxing out Concnetration, Diplomacy, Knowledge (Nature), Listen, Spellcraft, Spot, and Survival, thus freeing up other people's skills
The Wizard could be built many ways. More of a Buffer, or an offensive caster specializing in any school: Conjuration makes sense, as would Evocation, Necromancy, or Enchantment.
The Fighter/Rogues are going to be a little different. They get to use their extra movement to help Spring Attacks go off all over. In addition, they should use the Fighter Feats to focus on the Spiked Chain, giving the two Fighter Rogues plenty of Flanking Targets with the Druids' summonings. They can also evade Fireballs or Flame Strikes from their own party casters. The more Rogue of the two is probably using Weapon Finesse and has his Dex out the wazoo and plays like a pretty standard Rogue, though he is probably sacrificing some less important skills, knowing the other Fighter Rogue is covering 1 or 2. The Fighter, is probably going to use multiple feat trees to go along with a huge strength. He may even be the frequent recipent of an Enlarge Person to improve reach.
