It's only a way. A process to get a few people verified, like a tuna can, people who need it. To me these kinds of test are always like a joke. Like I said, social functions are not for fairness, but establishment. I probably can tell whose Chinese is cooler and makes me adore, if I were the examiner, but I can't ABCD them. Unless you take this thing seriously and proly enough like for the media, CCTV hosts or something. To me a man who masters a language is not a man brilliant at rhetorics and poem-like writing, having standard pronunciation, knowing all stories about the language, but who makes himself sexy by using that language. There are people, a homeless, a criminal, they acquire the native skills of their native tongue natively, I mean so compared to them, what's the point of you being bilingual at all? You can't be even as good as them to take a vocabulary test or something. The thing that makes you different from them is you use this language to make yourself unique, not to be common, unlike anyone of its native speakers.
Learn philosophy, man. Or at least like you say, keep interested. You'll see how vital languages are to human beings, and what kind of role linguistics plays since Saussure. It's a start. A watershed. At least for myself, I'm gonna have to work hard on them (which I haven't picked up learning) if I'm to be a good storyteller. Philosophy. Linguistics. Semiology. Narratology. And a couple more.