If you're grouping "up", then definately prioritize survivability over healing things. What sticks out to me when grouping with folks that aren't on the same gear level isn't when their heals/nukes land for less, but when they crumple & die under slightest pressure from a mob. Anything you can do to ameliorate that effect would put you on a much more even footing with people on a higher tier of loot.
specifics:
Get Call of the Wild immediately. Like, buy no other aa first. Completely unique add-on utility for shaman at 70, something you're expected to have. The first time it's needed and you don't have it... will be bad. The next 5aa you can beg, borrow, or steal should be in this activated aa.
Quickbuff 2 & Quickbuff 3 are different goals. When your overall count is low, shuffling the most expensive rank of this down a few notches in priority is really advisable. Quickbuff 3 is a good AA, but the marginal utility is not the same as the first two ranks, for 9AA.
Combat Stability will be better once your gear has progressed some. Postpone it on out of this stage.
Your mana pool is not superduper, for the content you'll be tackling. Spiritual Channelling ... is well and soundly over-praised elsewhere, but will honestly be invaluable to you in doing MPG trials, doubling your contribution.
Healing Boon is nice, but not an essential core enhancement. Goes after survivability and real healing AA.
If I were to prioritize the list you have above, I'd come up with this order for AA:
Call of the Wild
Spiritual Channelling
Combat Agility 2 & 3
Quick Buff 2
Lightning Reflexes 1-5
Virulent Paralysis 1-3
Healing Stuff (Gift 2&3, Adept 1-3, Advanced both)
Ancestral Aid 1-3
Spell Casting Subtlety 1-3
**EDIT** on those: middle, second, first, and end, respectively.
On Subtlety, as it turns out, you have the biggest de-agro multiplier in the game already, called "crappy spell haste focus". The fact that your spells land slower does more to ameliorate agro than SCS 3 would, if your spells were faster. Not being sarcastic, this effect really makes Berserkers and Rangers mad, cause itemization is much more powerful than their Jolt spells/axes in controlling agro. Anyhow, as you gear up, SCS becomes somewhat more an issue, so that you can cast the debuffs early, and the damage in the middle, and the heals at the end, all without pulling agro. Not so much an issue when fights are over before you get to whatever you chose to do third.
