In my opinion, maybe a self hosted blog or Neocities [1] for public discussions. Perhaps self hosted Nextcloud [2] for sharing stories, emails, files with friends. A self hosted Mumble/Murmur [3] for end-to-end encrypted chat and small file sharing.<p>[1] - <a href="https://neocities.org/" rel="nofollow">https://neocities.org/</a><p>[2] - <a href="https://nextcloud.com/" rel="nofollow">https://nextcloud.com/</a><p>[3] - <a href="https://wiki.mumble.info/wiki/Main_Page" rel="nofollow">https://wiki.mumble.info/wiki/Main_Page</a> Use their dev snapshot. It is quite stable and can scale to thousands of users on a small VPS node.
Depends on what you want out of it. My biggest loss with G+ sunsetting is that there were some decent technical groups. I've not yet managed to get addicted to Reddit, but I'm guessing that's going to be as good as I'll get.
I'm starting to see more domain-specific Discord and Slack instances being spun up. While great for discussion, they're not so good for long-form informational posts...<p>In the end, I'll go wherever the rest of the folks who share my interests go. It (hopefully) wont be Facebook, but there appears to be no other far-and-away frontrunner at this time.