Something that could make Mastodon safer and more pleasant to use would be reply controls.
This would optionally allow users to specify who can reply to their posts, so that people who experience abusive replies from bigots, trolls etc can pre-emptively prevent that happening.
It would also give people a middle option between follower-only posts and public posts.
If you're comfortable using Github, you can vote for this by giving a thumbs up at https://github.com/mastodon/mastodon/issues/14762