Zarkon is egotistical, too egotistical to ever bind himself to the Arch Mage, so when his powers developed he fled to Arkekk for sanctuary. He is either or sees himself as nobility/royalty.
He sees himself as a great leader but in reality he is not the best at dealing with people even with his social skills, thus his specialization in astral constructs (he can lead them however he wants because they have to obey his orders). This probably has something to do with his being paired with a Warforged.
Hmm, I don't have much else right now.