Pretty sure the "last damage taken" modifier in Misery only augments Cura and Banish. Auspice I think works in it's full form just by being in Misery stance. But yeah, it will be interesting to see how it all plays out. Perdu Wand got better with the low delay since we have Enlight now.
There is reason to be in either stance honestly. They both offer some unique things, so it will be an interesting trade-off. Your idea on NIN mobs in Dynamis is also one I thought of, but it just seems like it's still a bit of a sacrifice. Most times only 1 or 2 NINs will actually get Mijin off, all the rest of the times when they don't, switching to Misery just erased your Solace HP cured bonus. So, it will all depend on how long it takes to build up that bonus at 75. Hopefully it's not too bad as I'm assuming you lose it anytime you zone, or when 2 hours pass at maximum. Also, it all depends on how good the Stoneskin bonus is and how long it takes to rebuild it to maximum effect.
Also, Solace has the Barspell bonus, so you can't exactly say it's always better to switch to Misery when encountering heavy AoE. Probaby casting Barspells, then switching to Misery will be likely. It's also not really clear if Barspells increase gradually based on the HP cured bonus or if they are just better by being in Solace alone, so that will effect how much you could switch back and forth effectively. It basically all depends on how good Cura is. It may be mainly intended as a light cost cure to help take the pressure off when you melee. If it's cheap enough, could probably use it to wake up a slept party cheaper than Curaga 1, regardless of what stance you are in.
I'm also wondering how Sacrifice will end up working, as it's the only new spell at full capacity in Solace. I'm hoping it's more than just a way to steal sleep from someone and make everyone laugh. I Posted this awhile ago about Sacrifice. It says that being in Solace lets it remove more than one effect at a time, so that seems to be the main bonus besides it's usage to help Esuna. Here is a list of all the main TP moves I found that stack on multiple effects that we might not mind absorbing.
Edited, Apr 6th 2009 6:07pm by JingWoo
Trolls - Enervation: Defense Down and Magic Defense Down: Area
Uragnite - Suctorial Tentacle: Poison/Bind: Single
Proto-Omega - Hyper Pulse: AoE ~300 damage, Gravity and short Bind
Proto-Ultima - Chemical Bomb: Frontal cone AoE Elegy & Slow II effects
Blindside Barrage: INT & MND Down: Single (Only used in CoP areas)
Broadside Barrage: STR & VIT Down: Single (Only used in CoP areas)
Then of course, any other area where the AoE effects add up faster than you can erase them. One in particular comes to mind.
Aegis Schism: Defense Down: Single
Dancing Chains: Drown: Area
Netherspikes: Bind: Front
Barbed Crescent: Accuracy Down: Single
Or Bats in Einherjar stacking Attack Down, Defense Down, Evasion Down faster than you can erase.
In addition, anytime you want to use Esuna if the effect didn't hit you. Tribulation obviously would probably be best to Sacrifice/Afflatus:Misery/Esuna. Slowga in Dynamis if Divine Veil Erase isn't up, this would be much faster. Or Graviga, Bindga. But yeah, it's a strange spell.
And finally .... a small chance that it removes something new entirely like Terror, Amnesia or Weakness.