I have to agree with Kalistos in this.
If someone from the age of 20-33 becomes all these:

King Of Macedon
Hegemony Of All Hellas
Pharaoh Of Egypt
Son Of Ammon
King Of Kings of Asia
Maharaja Of The Indus
and in the end
Olympian God

He has to be a Genius to achieve it! and of course a bit of an ecsentricism!
So yes from that aspect Alexander was a nut case, but Reading his story and acheavements leaves you with the Idea of a Great Persona that had great Ideals and a lot of Vengence in him.