I'm currently using anki just for English, so I'd be interested in what you found harmful.

My more recent failed attempt to get an Anki habit going involved using Vim and a text file to input cards, instead of the tedious Anki GUI. I write lines of three tab-separated sections into the deck text file, with the first being the question, the second the answer and the third the card tags. Anki's import will ignore lines that start with # as comments. This lets me do batch editing of the cards using the macros, search-and-replace and block editing functions in the text editor. Problems with this approach is that I need the Anki software to preview my Latex formatting and I need to write raw HTML into the import if I want to use formatting or images. Anki should support card text with newlines if it's enclosed in quotes, but I don't seem to have cards using this in my example deck. Another problem is that Anki uses the question field of the card as a primary key and keeps the old deck when importing, so if I edit a question in one of the cards, I'll either need to completely regenerate my deck from the txt source or manually delete the card with the old question from the Anki database. As a Vim-specific tweak, my text file has the modeline [...] This disables physical autowrap of long lines, ensures that pressing tab emits physical tab characters and makes long physical lines visually wrap at the word break and indent the continuation of the physical line on the next visual line by two spaces so it's easy to tell apart from the next item. The text file approach does not store the review data for cards, to if I should lose the Anki database, I could reimport my deck but would have to go through all the cards with zero review data. More experienced Anki users can maybe tell how big a problem this would be. For all this interest into making the thing technically nice to use, still haven't found a suitably big and growable set of stuff I want to memorize to bother with the habit.