I have found that exact composition of the party is not really that important. Statwise, you should be able to make anything work regardless.
The important thing is making sure that the characters have a reason to be working together, or at the least making sure you can have fun even when you are NOT working together.
We have played a bunch of campaigns since 3E came out. The best ones have involved parties that worked well together, and never focused on party balance.
Forgotten Realms:
Ilsem, Human Evoker Specialist
Drake, Human Bard/Assassin/Fighter (in that order)
Rurik, Dwarf Fighter/Warmaster
Lucian, Aasimar Aristocrat/Spellfire Weilder
Ferryn, Human Psychic Warrior/Fighter/Duelist
Damian, Human Fighter/Sorcorer/Spellsword
Looking at the party, you would probably think that it wasn't built to be a wrecking crew. Perhaps this would be true, but there was not an encounter that they couldn't thresh through in a pinch, even if it should have been way to difficult for them. The versatility was just amazing.
This group got along because they all had similar goals, with only the Bard as a healer, we relied a bit on avoiding and dishing damage in fights, but it was a great campaign because we focused more on the goals of the group instead of fighting constantly. It helped that half the party was Sembian, and the group dynamic was actually improved by Ilsems Waterdhavian arrogance being taken down by the equally arrogant Sembians.