Here are my Limit Break 3 ideas. Limit Break 2 and 1would be downgraded versions.
Warrior: "Undying Fury" Red rage aura
Marauder: "Blocking Blades" A whirling set of axes float around those effected in a parrying/blocking fashion.
Paladin: "Celestial Intervention" Energy Angle folding its wings around those effected
Gladiator: Fine as is except 3 shields for LB3, 2 shields for LB2 etc.
Monk:"Dim-Mak strike" The monks jumps up striking a pose as their hand energizes to the point where the energy encompasses the entire forearm and hand and makes an energy fist around it in a matching pose before plummeting into the target.
Pugilist: "Flurry of Blows" Many strikes hit the target (Think Tiffa's limit breaks!).
Dragoon: "Dragon's Fury" The dragoon jumps up and lands on the upper neck of dragon and instructs it to breath a laser-beam on the desired target.
Lancer: "Scurrying Fury" The lancer draws many lances impaling the target many times ending with a finishing high jump strike with a bright white light fire effect.
Bard: "Moogle's Fervor" A collection of moogles dance around the targeted area healing those there with the king appearing raising those fallen.
Archer: "Fighting in Shade" The archer fires a flurry of arrows but none of them leave the bow till the end like it was being viewed in slow motion. A host of arrows burst up into the sky making the targeted area vastly darker blocking all sky light/s before striking.
White Mage: "Celestial Revelation" The same angelic beings from the paladin limit break appear with their wings folded spinning and opening their wings reviving all in targeted area.
Conjurer: "Natures Fervor" An elemental matching the weather condition appears reviving and healing those in the targeted area.
Black Mage: "Darkness Beacons" An arcane symbol appears in the target area summoning many dark portals on those effected followed by a large ovioal portal in the center initiating a dark explosion bloating out the light for an instant.
Thaumaturge: Similar to as is, flury of many asteroids.
Summoner: "Dragon's Breath" Bahamut's head drops out of a portal breathing fire on the targeted area multiple times with the increasing size and intensity. First being a bright yellow/white flame, second being orange flame, and third being violet in color.
Scholar: "Fairies Favor" A fairy appears those fallen raising them with dust dropped on them.
Arcanist: Fine as is but with a portal similar to the Summoner's limit break.