Preheat oven to 350 degrees F. Generously coat a 9- x 5-inch loaf pan with nonstick cooking spray.
Using a handheld or stand hand mixer, beat together 2 tablespoons of softened butter and the cream cheese in a large bowl until fluffy. Add the granulated sugar and beat until well incorporated. Add the egg and mix well.
In a separate mixing bowl, combine the flour, baking powder, baking soda, and salt. In another bowl combine the mashed bananas, milk, 2 tablespoons rum, lime zest, lime juice, and vanilla extract.
Using a wooden spoon, alternate mixing the flour mixture and banana mixture into the creamed butter mixture, in increments, until all of both have been added and it is well combined. Fold in ¼ cup pecans and ¼ cup coconut. Pour the mixture into the prepared loaf pan.
Bake in the preheated oven for 55 to 60 minutes, or until a toothpick inserted in the center of the loaf comes out clean. Remove from the oven and allow the bread to cool for 5 to 10 minutes in the pan, then transfer loaf to a wire rack to continue cooling.