We could bring back support skills in a meaningfull way. Why give eveey healer such homogenized tools? Point blank aoe heal, single target heal and stronger single target heal.
The most unique healing spells are rarely used or have long CDs. Im talking about Cure 3, Excogitation, Synastry, Plenary Indulgence, Horoscope.
They have all unique and interesting effects/ conditions. Make more of those!
Hell even Sacred Soil/ Earthly Star/Asylum type of heals.
Imagine fields of healing that pulse and heal everytime you cast the appropriate spell. Imagine a heal/shield that jumps around your party after it is spent. Imagine proximity based heals that become stronger the closer you are to your target. Imagine placing a dot on your target that causes it to heal the players attacking it. Imagine giving everybody in your raid an enchantment that causes them to drain HP off their targets.
More interesting healing mechanics please.