I’ve been here for awhile and have a pretty good understanding of how federation works. Number (3) was a very concise way to explain how the All feed works. I sort of knew but that really helped me understand.
Number (7), I will suggest the use of the cross-posting feature. Post to the larger community for engagement but also cross-post to the smaller communities to help them grow. Quiet communities are a cat-and-mouse game where people don’t post or comment because no one else is. The more people start to engage, the more others will start to engage.
Why cross-post to the same community this was already posted to?