Two questions: Is there any plan to add the ability to collapse comment chains? That's, like, the one big UI thing from Reddit that I'm missing. The other question is, is having the comment box for adding a top level comment at the bottom an intentional design choice, to encourage people to read the threads before commenting? I think at the very least adding a shortcut to take users to the comment box near the top would go a long way to improving usability.
Other than that, if the goal is to be a replacement for Reddit refugees, my first impressions are that this has the right recipe. Very impressive work so far.