I love that the last book gave us a glimpse of the last two couples, the youngest of the Grant and Ramsay siblings.  While the romance was great, the relationship between Alex and Jennie also turned me into a puddle.  This series consistently has strong female leads, but in a way that's nuanced and doesn't rely on "not like other girls" to make them stand out, and I really love that.  Also the men turning into ride or dies for their women brings me so much joy.