Here's my take.
My main toon is a lvl 65 mini and I consider myself a competent healer, so I'll start with our new healing abilities. Keep in mind that I have not had an opportunity to do true group healing and that such opportunity could easily alter my opinions; however, I have done experiments in solo skirms with what should theoretically be possible.
As has been mentioned the healing rating of our base heals have been nerfed and their power costs increased dramatically (though the power costs are continuing to be adjusted down). Also, as has been noted there are new instrument adjustments for power costs and if you're 4 traited in Protector of Song, you can stack three ballad buffs for -18% power cost on non-anthem skills.
In addition, we have a number of *new* heals to suplement. While in "Melody" stance (no stance), our coda does an insta-cast heal equivilent to BC with a lower power cost. Our non-damaging ballad does a small AoE heal. We get an improved Cry of the Valar (the old anthem of the valar) (lvl 74, I think) that provides a small fellowship HoT. There's also an Improved Chord of Salvation (lvl 72) that provides a small fellowship HoT.
If you switch to Harmony stance, the Coda changes into a combined AoE damage/heal, with the heal being slightly smaller than Inspire Fellows.
Now for buffs. It's true that we can no longer run a tale, pop a few ballads and maybe an Anthem and suddenly be running full group buffs. Instead, we have to selectively choose a smaller number of stronger buffs. For instance, the new Anthem of War provides all of the increased damage bonuses that the three tier 3 ballads used to provde. Anthem of prowess covers resistance mitigation (a stronger mitigation, mind you) and also a tactical defense bonus. The Anthem of Composure provides *group* -10% attack duration, in addition to increased armor and evade bonuses.
Also, do not forget that Anthem of the Free Peoples now modifies the Coda to provide a morale HoT to the caster and the Anthem of Composure modifies the Coda to provide a *power* HoT to the caster, *and they stack*. You can trait to modify anthems from 10s duration and 20s CD to 20s duration and 5s CD, allowing you to keep three anthems (and three Coda modifiers) running at any given time. So, if you're in Harmony, you could fire up AotFP, AoP and Anthem of Compassion (which modifies the coda to generate no threat) and in one coda, provide yourself with power/morale HoTs, heal your fellowship a small amount, damage all nearby enemies and generate no threat.
So the days of being able to get through most content by spamming BC and Inspire Fellows are gone. Instead, we'll have to be much more attuned to the pitch of battle and the needs of our fellows to be most effective. In short, I think *skilled* minis will be more effective in both healing and buffing; while less skilled minis will be increasing the repair costs of their fellowships a lot more.
Lastly, I really think the class revamp warrants increasing the class difficulty as I would say being a skilled mini will be at least as difficult as being a good RK or Warden.
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