I mainly use mouseover macros for healing. With those I can just hover my mouse over the person's name who I want to heal on the party list (or the actual player character, but I don't find that very practical) or if I have a monster targeted I can use it to heal the person the monster is attacking. The macro structure is:

/ac "Cure" <mo>

I use that with all my healing spells, have the main boss as a focus target (shift+F) to see what moves it's using and target the monster the group is currently attacking.

Hope this helps!