Healing is easier using the keyboard and mouse.... Clicking on a name and clicking on an ability is faster than toggling the ability and then toggling the name.
Controller is awesome for crafting and gathering. It's also great for melee classes. However, I find myself being more efficient with a keyboard. If my scroller is on ability 7 and I need to get to ability 2, I need to toggle/scroll through the abilities. On keyboard, I just click on 2.
To each his own, and this is coming from someone who used a controller exclusively in FFXI and FFXIV. I switched to keyboard/mouse because healing was not efficient. I have room for both in my FFXIV life.