Actually, he did change considerably, as it's been pointed out many times, even in this latest patch - (paraphrased) "he got used to talk to people, rather than at them".
ARR Alphy was a snobby arrogant brat that thought the world would bend to his every whim, he had good intentions and leader/diplomat skills, yes, but he only saw what he wanted to see and couldn't care less about anyone else's opinions, and that's why the betrayal of the Braves hit him so hard - it was the harshest wake up call he could face.

In short, his ideals and goals didn't change, his personality and how he approach people did.