I hope your article helps a lot of people. One thing I would add is that it’s also very useful to immerse in the new language by reading news in that language before you read the news in your native language. As someone who could scrape by in French, I decided to use my year in Lausanne to immerse myself in French. So my news comes from France24 and L’Obs, I watch only French series on Netflix (sans subtitles now, as the discrepancies between what the actors were actually saying and the lazy French subtitles were driving me crazy), and I read only French books. Of course I have lots of daily interactions with all the French-speakers around me, which helps reinforce and motivate me too. But also don’t discount “conventional” study — nearly every day I come across some twist of French that sends me back to the grammar books so I can add a new possibility to my repertoire.