A few comments:
1. To other commenters, as with the HN Vue demo a week ago (https://news.ycombinator.com/item?id=14284877), the project is a technical proof-of-concept; the aesthetics aren't the primary focus.
2. The Algolia API is better for scraping because it allows for bulk requests, unlike the official API (my old 2014 script still works I think: https://github.com/minimaxir/get-all-hacker-news-submissions...)
3) How much time did it take to manually label the training/test set before training the RF classifier? Even with topic modeling for extrapolating tags, accurate labeling for 20,000 submissions is a task.