How about this: A conflicted half-elf ranger/fighter who's seen as the leader of the party but who constantly doubts his own ability to lead.
A middle aged dwarven fighter...with axe and "darn those young'uns but I have a heart of gold that you can't see because.....GET OFF MY LAWN!!!" personality.
Twin human brothers: one a hulking fighter, and the other a highly intelligent, and sarcastic, wizard. Try to make as many references to "one person in two bodies" as humanly possible.
A human cavalier who's ultra-serious for his young age and might as well have a tattoo saying "Tragic Hero" from the moment you say his name.
A fun-loving halfling rogue who's as apt to annoy the party as hurt the enemy.
You can have multiple NPCs that can step into PC rolls when the tragic cavalier dies heroically or when the wizard separates himself from the group to further his own dark ambitions or just to provide different points of view to the overarching conflict.
....yeah, you can guess which books I've been re-reading recently, huh?
