For me, it's Leave a Trace by CHVRCHES. It's nice and calming, but also a bit retro. And I like the lyrics.
Let It Go - Idina Menzel. It reminds me of myself and of everybody. It reminds me of such a beautiful film. I recommend everybody to listen to Let It Go. It's a song which gives you power. Pay attention to the music and the lyrics.
I completely agree, never was a fan but his new album has some really catchy songs and I think 'Love Yourself' is the best one. And to answer the question, 'Stay' by Sugarland.