Instead of categorized instances (where communities are related to each other's interests) (but I have seen people who don't like the idea stil it's ok), I have another idea of an "Admin's Choice/regional/neighborhood" feed aside from my "subscribed", "local" and "all".
An "admin's choice" feed is where admins of an instance can promote approved posts/communities outside their governing instance upon their interests/preference, as an addition to the local feed, but it does not include all other posts/communities not in theirs. For better clarification:
"Subscribed": Communities/Posts (whether within or outside home instance) that I subscribe.
"Local": Communities/Posts that the home instance has.
"Admin's Choice": Communities/Posts that the home instance has + the outside communities/posts that the admins want to include.
"All": All Communities/Posts (whatever federated instances have, whether within or beyond the homes's preference) as long as the home instance connects to.
I realize when I browse other instance through their URL literally, every instance has own somewhat taste/personality of communities and posts done by the users joined in the instance. That's why I pop another idea.
Buts:
Q1: "Why not subscribe to the community?"
A1: If I subscribed a very specific community just for a single and immediate post or event, my "subscribed" feed will provide also other unnecessary and complicated (somewhat critical analysis) posts from that community, which I will never look up to. I just want posts of my particular interest in case of somewhat significance.
a1: For an example: I'm a (assuming) music lover, I just want to hear about a music artist concerts but I don't want to hear moreover about other analysis/extra gossips about the music artist as I just wondering going his concert just to listen and jam.
Q2:... My brain's timed up. I can't think anymore contras further, so anyways. My bad if many.
Very sorry for not enough understood (and may never mind this idea of mine) as I hardly describe what I really mean from my mind to suggest.
May the odd votes be in your favor.