After seeing some other posts from OP I think his anxiety stems from the expectation that the tank and other party members should constantly be at, or near, full HP at all times and that's just not true. I have three healing jobs at 55, I main warrior, and I don't even start healing tanks until their health is around 50 percent unless something is going quickly, horribly wrong. Fairy heals, or cure/Benefic potency, mean healing them at greater than 50 percent risks wasting the healing toolkit you have to throw at them. And that healing toolkit, on SCH especially, allows for more downtime therefore more time to toggle cleric stance, put down shadowflare, and dot away.

Of all three healing jobs I'd say AST has the least time to dps due to card management and lack of good offensive skills so again, once OP gets to Heavensward I recommend switching to AST.