I posted a list of proposed character adjustments at a thread over at the GameFAQs Message Board for Final Fantasy IV: Complete Collection.

Proposed Changes:

Luca:
- Analyze has a dramatically increased success rate and allows you to view the Bestiary entry for the monster in the battle by pressing Triangle during its use.
- Analyze will lower the defense of any mechanical enemy.
- Big Throw has a shorter charge time.
- Luca has an inherent "Strong Against Machines" effect.

Calca:
- The effects of Jive are now selectable with charge times for each ability. For example, Binding Glare takes much less longer to use than Frost Blast. There is a chance that the ability will fail.

Brina:
- The effects of Dance are now selectable with charge times for each ability. The charge times vary per ability. For example, Haste Dance takes much longer to use than Cure Dance. There is a chance that the ability will fail.

Eblan Four:

- The damage formula of ninjutsu has been adjusted to make it more powerful despite the low intelligence of all ninjas.
- The Wheel of Elements damage formula has been adjusted and can now Break Damage Limit.
- The speed of all ninjas has been increased slightly.

Izayoi:

- Izayoi gains the ability to dual wield.
- Heal Pill is now instant cast. The amount of HP recovered by Heal Pill has increased dramatically. Heal Pill can cure Poison and Blind.
- Healing Salve is now instant cast. The amount of HP recovered by Healing Salve has increased dramatically. Healing Salve can cure Poison, Blind, Paralysis, Silence, and Berserk.
- The Frostwave Band has been changed to the Healing Waters Band. Izayoi and Leonora combine their powers to cure most status effects and restore HP to the party.
- The Phantom Lightflies Band has been adjusted to cast Healing Salve and Smelling Salts on the entire party.
- Izayoi gains a new band with Edge that revives a knocked out party member and grants them the Blink Status.
- Upon completing her individual mission, the Illusions ability can target the entire enemy party.

Gekkou:

- Gekkou gains the ability to dual wield.
- The damage formula for Payback Wave has been adjusted. Payback Wave will do additional damage if Gekkou is low on HP that is no longer based on exact HP amounts.
- Upon completing his individual mission, Gekkou's Throw ability becomes identical to Edge's Throw ability.

Zangetsu:

- Zangetsu gains the ability to dual wield.
- Human Kite has been adjusted to have a much larger charge time in the air, allowing Zangetsu to avoid enemy attacks for a prolonged period of time.

Tsukinowa:

- Tsukinowa gains a new band with Edge that casts Restore Weed on the entire party.
- Upon completing his individual mission, Tsukinowa's Steal ability has a dramatically increased success rate.

Palom:

- Bluff only affects Palom. Using it cannot set off any counterattack from the enemy party.

Porom:

- Pray has an additional chance to heal Poison, Blind, Paralysis, Silence, and Curse.

Edward:
- Edward's class has changed from Royal to King.
- The effects of Bardsong are now selectable like in the DS version of Final Fantasy IV. The charge time for each song varies. For example, Hastemarch takes much longer to cast than Life's Anthem. There is a chance that the song will fail.
- Healing Harmony has merged with Life's Anthem to restore additional HP to the party.
- Edward starts with the Economical Ring in his chapter.

Harley:

- Harley's class has changed from Secretary to Scholar.
- Piercing Sight now has perfect accuracy. It can dispel all positive status effects on an enemy target including Reflect. It has a slight chance to cast Libra and give the enemy a new weakness which will be displayed by the animation.
- Gil Toss has a modified damage formula allowing the attack to do much more damage based on the current Gil of the party.
- Harley has an inherent Gil Band v.2 effect.
- Harley has an inherent Economical Ring effect. This makes her able to use any recovery item at double potency.
- Any item that Harley uses that produces a magical effect in battle will be calculated as if she were the one casting the spell. This means items like Red Fang or Stardust will do damage based on her own statistics rather than a flat value.

Cid:
- Analyze has a dramatically increased success rate and allows you to view the Bestiary entry for the monster in the battle by pressing Triangle during its use.
- Analyze will attempt to inflict Stop or Confusion on a mechanical target. If successful, a message will be displayed showing what Cid has done.
- Risk Strike has become Upgrade. Upgrade allows Cid to consume an elemental item to enchant the weapon of any party member including himself.
- Cid has an inherent "Strong Against Machines" effect.

What do you think?