Tough one. Vietnamese is definitely a unique language for me, it's the one I spoke at home growing up, with my parents, with my family. Not sure about writing a song or a poem however, for that it might not be the best, as my vocabulary can be a bit limited sometimes.
But yeah, in a family setting, it's definitely the one, and hearing Vietnamese randomly from time to time makes me happy instantly.
Maybe not the best example to follow
https://en.wikipedia.org/wiki/The_Tuxedo
Also, as we're on the Asian diaspora community, are you of Asian descent?