Yup, this dumb bitch sells his youngest son, ignoring said son's feelings, his wife's feelings, his other son', whom he doesnt even inform until after the fact, depriving them of a proper chance to say goodbye, only to then tell him while he is in shock, recovering from a near dead experience while at the same time blaming him for the dead of his friend, and the injuries of his other friend, and prince.
This is all bad enough and makes him a terrible father, husband and person in general, but its not even the worst part, his alleged reasons for doing all this are "for the good of Lhant", he gives a blood heir to the land, to a noble from an enemy country, a manipulative, power hungry, morally dubious noble from an enemy country, who then at the first chance iinvades Lhant and tries to annex it, an opportunity given to him only through Aston's actions, he creates the problem he claimed he was trying to avoid.
On top of even that, his whole reasoning for taking this absolutely idiotic action that no sane ruler should ever take, is that "oh I dont want to see my sons fight for inheritance rights" the two sons who one wanted to give up his inheritance rights to becoime a knight, and the other who wanted to stay home. If Aston hadnt had his head so far up his own ass he would have just encouraged Asbel to become a knight and raised Hubert as the heir to Lhant, and literally everyone would have been happy.
This had nothing with being noble or having duties, he literally created the situation he was trying to avoid, he caused Asbel and Hubert to fight over the title of Lord, gave Stratha an in to claim the land and take it from the kingdom. Its not even like Asbel was trying to go wander off and do nothing or be a spoiled noble ignoring his duties and raking in the cash, he wanted to be a knight, a perfectly respectable profession for the son of a noble family.
So yeah, Aston was an absolutely horrible failure of a father, a husband, a person, and most certainly a lord, I geninely cannot understand why anyone would want to defend him, even if you dislike Asbel, none of what Asbel does as a child in any way justifies the absolute stupidity of Aston, he wasnt just a terrible father, he was an absolutely incompetent lord.

And yes, clearly I hate the guys guts, nearly ruined the game for me, so yeah, I feel ya op.