“To explain my thought briefly, the material with which a good is concerned is sometimes contrary to nature, but a good itself never is contrary, since no good is without reason, and reason is in accordance with nature.”
The fact that by defintion, indifferents are not goods, but the manner in which we handle indifferents can be is often overlooked. This is the basis of the ascetic training of Musonius, Epictetus, and Marcus. It’s well worth remembering.
It seems as if you are setting up three categories of goods, primary, secondary, and tertiary. It’s important to note, as you’ve said, that the primary ones are not more virtuous than the secondary, it’s maybe better to call them Type A, B, and C then primary.
– good children,
– the welfare of one’s country.
these become manifest only in adversity,
– equanimity in enduring severe illness or exile.
Type C: Certain goods are indifferent; these are no more according to nature than contrary to nature,
– a discreet gait
– sedate posture in a chair.
I’m going to assume these are descriptive categories, and not prescriptive types. In fact, I’d only want to call Types A and B goods per se. I’m pretty sure Type C misses the mark for Stoic criteria for goods. I’m sure certain folks, or parts of society, would call Type C goods, but a philosopher should not, as you note: they’re indifferents.
The issue might be one of terminology, the common use of good and the philosophical. Despite the already jargony nature of Stoic discourse, it might be better to use the Greek for these words: ἀγαθός (agathos) — good or καλός (kalos) — beautiful, good.