Books that I have used during my "search for understanding" are 1. Devotional Classics by Richard Foster and James Bryan Smith, 2. "In the Heart of the Temple" by Joan Chittister and 3. "Strength for the Journey" by Peter Gomes
Devotional Classics is 52 essays and sermons by the likes of CS Lewis, Thomas Merton, Henri Nouwen, Dietrich Bonhoeffer and many others. Many parts are quite conservative but worth a look.
In Chittisters book there are 16 short essays regarding many spiritual disciplines.
Peter Gomes' book there are 22 sermons about Themes of daily life and 18 sermons about Liturgical Seasons