Greetings: did you forget to add salt? It is necessary to balance the sugars, and also for proper rising.

Morning Cleve! This is a family recipe that didn’t include salt but you can definitely add 1 tsp to the dry ingredients for the reasons you mention. Here are two other coconut cakes on our site that add salt if you’d prefer one of these:

https://food52.com/recipes/72786-coconut-caramel-sheet-cake-layer-cake

https://food52.com/recipes/46436-coconut-layer-cake