Jumping into the conversation late, but I've only recently been putting any real effort into running an atonement spec now that 4.06 is here, and was looking for some feedback.
So we all know by now that atonement priests reign supreme as tank healers on halfus, but I'm trying to figure out how to keep myself useful in encounters that don't favor atonement healing specifically (Halfus seems built for us in particular). I've found myself slipping into the role of bubble generator quite a bit outside of that encounter (I'm including aegis here). http://us.battle.net/wow/en/character/thunderhorn/bluntrauma/talent/primary
I've been using this spec with glyph of smite to buff my atonement heals by another 20%. The problem is that in order to dig deep enough into shadow to get 2 points in Twisted Faith, I have to sacrifice empowered healing altogether. For the record the extra hit is to make sure that Holy Fire doesn't miss.
Speccing into Twisted shadows means I have to sacrifice empowered healing or divine fury. I've played with both and found that divine fury gives me better throughput as a primary atonement healer, but I hate leaving a 15% buff to my straight healing spells on the floor (although fortunately my PoH isn't affected). With my current spirit, 1 point in twisted faith should be more than sufficient for raiding purposes, and I'll check that out next week.
Healing as atonement requires dps gear. I know it sounds crazy, but just for kicks I asked a spriest buddy to try out a similar spec to what I currently have since he's geared for shadow priesting in mostly 359 epics. Several things became instantly obvious.
His smites are faster, hit harder, and therefore his atonement heals are much bigger.
This isn't really a design problem so much as gearing problem. I'm having a hard time justifying bidding on dps gear in order to be a more effective atonement healer, admittedly a very niche spec at this point.
So I've been thinking, as a lot of us have, about the changes I would make to atonement healing, and priests in general, to make atonement healing more viable overall.
1. For starters like a lot of people are saying, allow grace to stack from atonement.
2. Redesign atonement to allow it to proc off of all of our holy/disc dps spells.
It'd be nice to see other healing procs off of other spells, specifically holy fire and penance. I know penance can be used either way, but I'd love to see it used similarly to smite.
3. Change the uptime of holy fire so that it actually matches the cooldown. Holy Fire ticks for seven seconds I think, but the cooldown is ten, which means at least one smite isn't healing for it's max value, it just seems a bit counterintuitive.
4. Bump Twisted shadows up into the first tier of the shadow tree. Should be self explanatory.
I want to say that I think blizzard has done a great job with discos in cata, and priests overall, but I still feel that disc isn't quite there. I find it odd that if I'm going for max absorption I'm better off avoiding evangelism and atonement altogether and speccing straight disc. This is due mainly to the unique gear demands of an atonement spec utilizing glyph of smite. I know that balance is always high on the priority list, and changing atonement healing in a manner I've suggested would make priests downright ridiculous in pvp, but it's just brainstorming. I'm also not saying atonement is broken, far from it. I think it's just a little bit ... sprained I guess.
Anyway, any feedback, theorycrafting on the subject of atonement, would be much appreciated. Cheers~!