I agree with the OP, and would like to add onto the thread by saying Kakashi is the only man to have, careerwise and emotionally, experienced every facet of the ninja lifestyle. He is the epitome of well-rounded.
Kakashi has experienced EVERY rank in the leaf ninja military. He was an academy student, graduated to genin, was promoted to chuunin, was further promoted to jounin, later became an anbu agent, and finally ended his career as the sixth hokage of the village. No one else in the village can make this claim.
Kakashi has experienced all of the pains that any other significant character has experienced. He lost his mother like Naruto, witnessed his father's corpse like Sasuke, experienced the pain of losing a friend (Obito), experienced the pain of killing a friend (Rin), experienced the pain of losing a teacher (Minato), experienced the pain of betrayal by a friend (Obito), etc. No other ninja can claim to have experienced all of these.
Lastly, skillwise, Kakashi is the most well rounded. That is to say, in every category he is able to use the famous line from GATTACA, "I was as good as any, and better than most." He loses to specialists in each field, but is generally better than those specialists in almost EVERY OTHER CATEGORY.
What do you think?
