Thanks for the comments, everyone, and feel free to ask questions here.
Some background: I started working on Vimflowy after a conversation with a friend. I'd seen many similar apps, but the vim part was important to me. I've tried the spacemacs org layer, but it didn't work out. My friend had a huge document on Workflowy which started getting laggy for him. Vimflowy lazy loads, and deleting and pasting large subtrees is efficient, which went well with the vim concept. So it started out being a tool mainly for me and my friend. At this point, I'd be happy if others found Vimflowy useful, though I don't have grand aspirations for it. I've tried to make it so that developers can customize it to their liking without much trouble. I would consider making a second set of non-vim bindings out of the box if enough people seem to like it - it'd be relatively easy to implement, but the space seems crowded enough as is.