Just a casual listener, mainly thanks to Terrace House (the original intros were Taylor Swift songs, but it changed to CHVRCHES for the new season and i'm fine with it).
So, the first series, B&G Next Door used We are Never Getting Back Together (can only find an extended fan montage on YT):
The cast even got to meet her in one episode, she was kinda seen as the godmother of the show.
New Romantics for B&G In the City and Aloha State seasons is the one I like the most I think:
They also often used a piano version of these songs for emotional moments and it was great.
Not a fan of the original Ready for it but I really like the arrangement for the Opening New Doors opening. It changes the mood of the song:
So yeah, that covers the Taylor Swift songs I like the most... oh and Shake it Off.