In general, as somebody who migrated from Reddit in June, I’d say that the best of us are already here. I’ve only run into a handful of shitty trolls here these past 4 months. The smaller userbase also results in fewer posts and comments, so I spend less time scrolling through endless content. Both of these aspects have led to me feeling significantly happier and present. You’re right about niche communities being too small here, but I would rather have it this way than deal with proudly ignorant, stupid, hateful dipshits relishing in being loud assholes in a thread with thousands of users learning to be loud assholes like them.
In my opinion, if people want Reddit, they should go to Reddit. The fediverse is the way that it is, and of course I’m open to improvements, but fundamental alterations to the entire identity is not something I would like to see. I’m happy to engage in discourse and disagree productively, which is much more possible here than it ever was on Reddit.