If I was to nominate the two things I find most striking about Mastodon they'd be:
1. the ability to edit posts after posting; this (as my followers will know) is a facility that I use a lot (and thanks to my great crew of typo spotters);
2. the norm of civility that we all maintain; of course trolling & slamming is not completely absent, but at least in my timeline & discussions/conversations civility have been the over-riding characteristic of my exchanges.
@ChrisMayLA6 I would like to add 3. Real human moderators. Only this week, I had to report several guys for harassment, hate, and one scraping our data. It took only a short time, they were gone.
But at the same time it's one of the weakest points (Mastodon is constantly working on it) because offenders change to instances without moderation, blocks are not real blocks, they can do bad things you don't see. Many write their hate by PM: it's hidden. They act with screenshots. It's a big problem.
@NatureMC @ChrisMayLA6 on mastodon is part of that, and it is a beautiflu tradition I value.