I still think Sei should learn to be less strict with other apprentices, he is too hung up on perfection.
But at the same time, he does need to be strict too, not denying the need for that, some people need to be put in shape or get out if they can't be serious about it.
But now that he will own his own place, he will learn it by himself, it is his own hardship to deal with now as the boss.