If you go SCH:
SCH since launch, currently getting slapped around in AS3. Currently sitting at 195 ilvl.
Keep Aetherflow on CD. Burn it on Energy Drains if Lustrate/indomitibiliy would be a waste.
Pair Rouse with Whispering Dawn, if running Eos.
Right now, during progression, your goal is to be in cleric stance and DPS as much as possible. Work with your co-healer to make that a reality.
Talk about when they need you to help heal, when they need you to switch to full time healing, and when they need your cooldowns.
Succor is largely worthless without being paired with Emergency Tactics. The mana you spend for the mediocre healing is not worth it when compared to Indomitability/Medica, just save your mana and let the WHM/Indo do it if Emergency Tactics is on CD.
Micro your pet at all times, no excuses. It should be on Obey, everything it casts should be controlled by you, and it should not get hit by any cleaves.
Dropping out of Cleric Stance to use Physic is a waste. If they need the healing of a single Physic, use embrace instead. Only drop out to use Aldo, never Phsyic.
This of course applies to spot healing random damage while DPSing. If you're in 'full on healer mode', use physic normally.
Your DPS opener is Swiftcast -> Shadowflare -> Potion -> Bio II -> Energy Drain -> Miasma -> Energy Drain -> Bio -> Energy Drain -> Aero II -> Aetherflow -> [Broil -> Energy Drain] - Repeat until a DoT needs reapplying.
You should get 6 Energy Drains off within your potion duration.
I've had AST at 60 since launch week as well. It's fun, very fun even, but it's nothing compared to SCH in terms of flexibility and performance. Obviously there's bias to what I'm saying, but objectively SCH just has more tools to work with, and provides RAW dps. I do my daily roulettes on AST.
For AST, use Luminiferous Aether as soon as you hit 75% mana, and keep in on CD after that. Your mana issues should be non existent.
Don't use Dinural Sect. Just don't.
Collective Unconscious is rarely worth using, only use it if there's light healing needed and you want to conserve mana. Celestial Opposition works on buffs you place on yourself, pair it with Luminiferous/Ewer.
Synastry is amazing, learn to use it. It's WoW Paladin's Beacon of Light, word for word, but it has a duration and a CD.
Wall of text, yada yada. I'll stop. If you wanna ask anything, shoot.