Other chief picks and choose their warriors, relying on stories and hearsay, relying on blood relations and closeness and while Aeryon does have people who is close to him in high position, all of those people could convince the people below.
A slave could be freed and become a Chief warrior.
A prisoner could win the appreciation of the Kan and freed and could always find himself in the favour of the Kan
Aeryon chooses such a way and all of his soldiers are motivated.
The merchants rights are protected and merchants flocks to his city, raising wealth and increasing the prosperity.
The wealth is distributed and the economy moves.
The economy moves and the people become prosperous.
The people are happy, innovation then would slowly arise.
Innovation leads to convenience but also to strength.
A virtuous cycle is formed and if there is corrupt forces trying to corrupt his virtuous cycle, Aeryon could still control it.