I am picking two of the boldest choices she could make - LINLYA or WINKIAW.
Like i'll never love you again - three months ago i would have said choctaw county affair but after seeing LINLYA live at CMT AOTY I think it would be a lovely, bold choice. I also see that the "Love Junkies" have become increasingly popular and that McKinnon lady keeps winning Song of the Year. Carrie's gorgeous performance - combined with her adoration for Mike - would make this lovey, gooey mess that I love hearing.
WINKIAW - Again, bold & deeply personal, it would get Carrie out of her comfort zone and reveal more about the woman behind the songs. Easy video to make. Just show lots of Isaiah, people would eat it up. Plus, it's a memory Isaiah can look back on when he understands more about what Carrie did for a living while he was growing up. And i think it woukd perform better than MS - despite sounding minimally country.