Thanks to Petite on ULMF. the words in () are my comments)
Brynhildr: recovers cost when defeats enemy; being defeated is treated as a full cost recovery retreat.
(Doesn't count against you when they die AKA against your three star. In addition you don't have to worry about the withdraw at all because you will get your UP back regardless.)
Bandit: attack-up against armour-type and high defence enemies.
Berserker: attack-up against armour-type and high defence enemies.
Destroyer: attack-up greatly against armour-type and high defence enemies.
(Previously was only damage up against armor-type enemies. Now it applies to high defense ones as well)
Mage: wide AoE magical attack.
Warlock: wide AoE magical attack.
Arch Mage: wide AoE magical attack.
(I am assuming their AoE just got bigger... witch means Garania's attack while her skill is active would probably hit the entire screen... or a large portion of it.)
Summoner: possible to use token; attacks with summon magic while skill is active.
Summon Master: possible to use token; attacks with summon magic while skill is active.
(When did they get token? Oh well now they can deploy them while their skill is active)
Sailor: attack lowers enemy movement speed while skill is active; possible to deploy again after time has passed when retreated.
Sailor Chief: attack lowers enemy movement speed while skill is active; possible to deploy again after time has passed when retreated.
Sailor Elite: AoE attack that lowers enemy movement speed while skill is active; possible to deploy again after time has passed when retreated.
(Couldn't previously be deployed again after being retreated)
Avenger: attack-up depending on current HP; being defeated is treated as a retreat.
Death Avenger: attack-up depending on current HP; being defeated is treated as a retreat.
(Defeat wasn't treated as a retreat. Aka it does count against no dying allies)
Chrono Witch: lowers movement speed of all enemies within range.
(Had the slow of a normal witch)
Youko: able to evade attacks from enemies; attacks all blocked enemies; able to paralyse enemies after multiple attacks.
Tenko: able to evade attacks from enemies; attacks all blocked enemies; able to paralyse enemies after multiple attacks.
(Does not paralyse)
Parliamentary Secretary: adds 30% of base attack and defence to Prince within range; when Prince is defeated, revives once at 50% HP. (Currently 10% and she does not revive the prince at all)