Hi. I have the issue that most debated posts (anything liked, replied to) are outnumbering the most urgent posts (i.e. announcements) when digest emails are generated. So people get talked about things in their mailbox but not more useful/urgent stuff.
What would be useful is something like an option digest_posts_from_category_priority for the digest email setting.
Here’s the full picture: on our Discourse, we have one category “Announcements” with several Topics based on the type of announcement to share (ex. T1: “Event”, T2: “Jobs”, etc.). All users can post their announcements in these topics; and are as well restricted to make new topics. This is the most viable setting we found so far in order not to “pollute” the latest feed with announcements.
Now, announcements are super useful (opportunities) but not often liked or replied to. So they are almost never included in the digest email. Something which in the long run degrades the aura of the forum, when people just find out that they missed stuff 
N.B. There’s the option to track the “Announcements” category by default for all users, but this is in our circle considered too close to spam.
Thanks for any help about this (: