Thank you, guys!
Can I get an expert's opinion on how to approach these:
1) Disable the blog for individual users. Blogging will be done by specialized users (owners of specific groups)
OR
2) For normal/individual users, only allow them to set blog access to Friends or Private, so they may continue to use the functionality, but won't have their content show up on any other person's activity stream (except for their friends').
Blogs (aka News) only for admins and group owners: https://elgg.org/plugins/1640707. You can use the normal blog plugin in parallel to the news plugin. Or you could disable the blog plugin to only allow admins and group owners to making postings. The news plugin is based on the blog plugin, so even if you don't want to use it, it might give you some starting point for implementing your requirements.
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