As someone who always means to learn a bit of Latin and Ancient Greek, this is a very cool looking site -- the inflection tables and diagrams are an especially nice touch. One addition that I'd love to see (if technically feasible) would be some sort of drilling or practice mechanism, e.g. a cloze-completion generator (a la Clozemaster or Lingvist, or the I think quasi-defunct Readlang).

By the way, if you're ever considering classical languages further east, I'd call your attention to ctext.org -- it doesn't do anything particularly fancy with its UI, but it has a lot of classical / premodern Chinese texts, and classic English translations (largely Legge) of some of the major ones.