Make the cupcakes: Preheat oven to 350F. Line two 12-cup muffin tins with 15 wrappers. Set aside.
In a large bowl, beat butter and sugar until completely smooth. Beat in agave, eggs, yogurt, vanilla, pineapple juice, and banana until smooth. Add flour, baking powder, baking soda, and salt and beat on low speed until batter is smooth.
Fill prepared muffin tins 3/4 full of batter. Bake cupcakes at 350F 20-22 minutes until cupcakes spring back when lightly touched. Cool cupcakes completely on a wire cooling rack.
Make the frosting: In a medium bowl, beat cream cheese until completely smooth. Beat in butter until creamed. Add powdered sugar, vanilla, and orange zest to cream cheese mixture and beat on high speed until completely creamy. Gradually beat in just enough milk to make frosting a piping, spreadable consistency.
Pipe frosting on cooled cupcakes and store in refrigerator until ready to serve. Enjoy!