For reference: half of my school credits were in French and that's about the level of reading I've been at in French for a decade, most of "les romans français" ive read are <300 pages, and not anything mindblowingly difficult or antiquated, usually analized in literature-class format (essays, presentations, quizes on vocab/grammar/etc). Im looking to progress from there, hence the question. (My education is a Canadian "French emersion" one from a border-province.)

moreso wondering how something like fantôme de l'Opera compares to Monté Cristo in vocabulary, or if someone has experiences with originals v translation (in non-mastery / ECL C1 level) second languages, for advice or insight

ie: discussing the nuance lost vs ease of comprehension in translations. Which of the classics would be a good entry into 1800s French vocab, specifically. That sort of thing.