I want to take a case by case look at why I think many of the changes look great on paper.
WHM
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WHM maintains its excellent MP management tools and the lilies have been updated to provide some nice new toys to the WHM. The only thing the WHM really lost was Aero 3. Big deal.
Gained:
* Improved Plenary and Lily mechanics
* 2 new instant MP free heals
* New healing buff cooldown
* Big hitting AoE spell 4 or 5 times a dungeon
Lost:
Aero III
This just looks like a win to me.
AST
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In the majority of situations, most cards were not all that good. The usefulness of an AST in any given run was a mixed bag. This is REALLY true for dungeons (What the majority play) where you rarely needed tools like Bole or Ewer for any reason.
Now, every card is useful to someone and instead of playing a game with teammates (In terms of how much AST help them) AST fall more in line with other jobs and have a minigame to execute for nearly 100% positive results.
Other than the card rework system...AST lost...Time Dilation and Lord of Crowns damage.
Gained:
* A heal buff in Neutral Sect
* An AoE heal in celestial opposition (In trade for a stun and time dilation effects)
* An MP free AoE heal
*
Lost:
* Time Dilation (Now that cards will be available so often there really is not a need for this anymore)...RIP Enhanced Arrow/Time Dilation fun.
* Lord of Crowns damage (Changed into a buff)
In truth, I think AST, while less complex on the card system, is now far more approachable to the majority of players and will have some huge moments of feelings like a healing god. Oh yeah, Lightspeed and Gravity still exist. DPS will be fine.
SCH
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This is the one I think there is the most consensus exists about and I am most sympathetic (as a SCH main) to. Let's be real, SCH has had a full on identity shift. SCH traded AoE and some personal DPS tools for amazing recovery and prevention tools. There is no two ways about it, the DPS rotation of SCH is now simple, in exchange for more ways to make sure noone ever dies.
Gained:
* RECITATION! - This one cannot be overstated...absolutely a godlike cooldown that will allow SCH to reliably bypass mechanics.
* Excog on self
* An MP free AoE heal from the fairy
* INSTANT CAST FAIRY COMMANDS - Dear lord thank god. this will let the SCH reactively use the fairy to mitigate failed mechanics...especially with...
* Seraph - an pretty stellar buff to the fairy on a decent CD
* Art of War - AoE spam...pretty basic.
Lost:
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* AoE DPS tools - Ouch (Condensed due to char. limit)
* Energy Drain - This will shift some MP management to the fairy.
SCH will be fine for Trials and Raids. I imagine once people get decent with their new classes, this will be the least preferred dungeon healer because the AoE DPS potential just really is not there and is boring as sin. A DPS spender via Aetherflow would go a long way.