So with all of the MSK ideas floating around out there, I'm still more intrigued by other jobs. This is one that I've been developing, on and off, for a little over a month.
THF is your basic positional mDPS class (which seems to be a requirement for mDPS in ARR). It has a couple of DoTs that are required to maximize the damage on one of the combos. The basic expected rotation is Flurry>Hemorrhage>Cheap Shot>Eviscerate, which should have both DoTs, the piercing debuff, and the Flurry buff maintain 100% uptime (15% attack speed increase = 2.125 sec base GCD; 8 * 2.125 = 17 seconds). The complexity is going to be in the substantial amount of bouncing between flank and back required. The average potency per (standard) GCD is going to be around 399.70 (including 83.33 / .85 from auto-attacks and assuming 1 Gil Toss every ~8.2 seconds, based upon Mug and Pilfer). When you hit NIN and replace roughly half of your Shurikens with Katons, it goes up to 412.57 (which is right around what MNK and DRG manage now).
THF will wield a brace of daggers/ninja swords (largely aesthetic difference, much like the difference in the various size swords/shields) that would have very fast auto-attack speed (~1.5 sec; daggers are faster than ninja blades) and use the same armor as BRD (DEX based light armor).
The THF gimmick is the Ill-Gotten Gains resource, which is gained by using Pilfer on a target or has a chance of being given to you when you score a critical hit. Ill-Gotten Gains is an abstraction of the stuff that a THF steals and, when you hit NIN, ninja tools that have traditionally been consumed by throwing.
A lot of the THF utility is built around mobility. Lots and lots of Mobility. Flee and Tumble are both on comparatively low CDs and give you a lot of mobility with a healthy bit of survivability wrapped up in it as well. A lot of THF abilities have this kind of thing going on, where they have multiple disparate types of functionality folded into the same (i.e. survivability and damage, utility and damage, or utility and survivability together).
Random note, all of the evasion buffs are ignored by the primal signature attacks, just like Hallowed Ground, so they can't really be used to cheese spike damage mechanics and don't have anywhere near a high enough uptime to make the class a viable tanking option.
Thief Abilities:
1a. Pilfer: off-GCD, 30 sec CD; 5y range, grants Ill-gotten Gains, infinite duration, generates no enmity
1b. Gil Toss: off-GCD, 120 potency, consumes Ill Gotten Gains
2. Disappear: reduces enmity by half and causes next attack to automatically score a critical hit, 10 second duration, 60 sec CD
3. Quick Stab: 150 potency
4. Flurry: 100 potency
Flank bonus: increase attack speed by 10% for 18 seconds
Combo Action: Quick Slash
Combo Bonus: 190 potency
5. Backstab: 100 potency
Back bonus: 190 potency
6. Cheap Shot: 100 potency
Combo Action: Backstab
Combo Bonus: Damage over time, 25 potency, Duration: 18 seconds
7. Ambush: 50 potency
Flank bonus: 100 potency
Combo Action: Backstab
Combo Bonus: 230 potency
Additional Effect: reduce target's resistance to piercing damage by 10% for 18 seconds
8. Eviscerate: 100 potency
Back bonus: 150 potency
Combo Action: Ambush
Combo Bonus: 75 potency additional damage for each of your Cheap Shot, Hemorrhage, and Hamstring on the target
9. Hemorrhage: Damage over time, 35 potency, Duration: 18 seconds
10. Spinning Strike: 360* AoE, 120 potency
11. Hamstring: 50 potency damage; Additional effect: target is slowed by 50% and takes damage over time; 15 potency, Duration: 18 seconds
12. Trick Shot: Gain the benefit of all positional effects regardless of your current position; duration 10 seconds; 120 sec CD
13. Tumble: Leaps forwards 10y; 30 sec CD
14. Flee: Increases movement speed and evasion by 100% (does not work on signature attacks) and reduces damage dealt by 100%; Duration: 5 seconds; 45 sec CD
15. Artful Dodger: Increases evasion and Dexterity by 10% for 15 seconds; 120 sec CD
16. Master Thievery: Deals 150 potency for each stack of Ill-Gotten Gains you have; 60 sec CD; consumes all stacks of Ill-gotten Gains; off-GCD
17. Distract: Reduces accuracy of target and all enemies within 6y by 10%for 10 seconds; 45 sec CD; consumes Ill-gotten Gains; off-GCD
Thief Traits:
1. Enhanced Pilfer I: Pilfer range increased to 10y, max number of Ill-Gotten Gains stacks increased to 2
2. Mug: 20% chance on critical hit to gain 1 stack of Ill-Gotten Gains
3. Enhanced Hemorrhage: Duration on Hemorrhage increased to 30 seconds
4. Enhanced Flurry: Increase effect of Flurry to 15%
5. Enhanced Pilfer II: Pilfer range increased to 20y, max number of Ill-Gotten Gains stacks increased to 3
6. Improved Trick Shot: Reduce the cooldown on Trick Shot to 90 sec
7. Enhanced Dexterity I: Increases dexterity by 2
8. Enhanced Dexterity II: Increases dexterity by 4
9. Enhanced Dexterity III: Increases dexterity by 6
10. Enhanced Artful Dodger: Increases effect of Artful Dodger to 20%
11. Enhanced Flee: Flee now restores 20% of max hp
Ninja is based heavily around giving you additional uses for your Ill-Gotten Gains. Mirage is another one of those multi-function abilities that provides both survivability and damage, which is based off of the classic ninja body replacement techniques. Katon, Raijin, and Fuujin are the 3 most elementally appropriate Ninjutsu techniques, based upon their elements (fire, wind, and lightning as opposed to ice, water, and earth), which is why I went with them instead of the others. Grand Lethal is a big nuke/buff which follows the same "dual function" mold, even if it's just based around exploding enemies. While it's not a *traditional* Ninja ability, I stole it from Zidane and thought that the name/effect seemed pretty appropriate for a crowning ability for the NIN.
The relic weapon would be the Orochi, a weapon wielded by a traitorous ninja of old that went on a killing rampage before finally being killed by his best friend, who sacrificed himself to impale the both of them with the weapon during the battle. The bloodstained blade remained in that ancient battleground in the mountains of Coerthas along with the bodies of the two ninja, lost to the ages.
Ninja Job Abilities (THF, PGL, ARC):
(Gil Toss changes name and visual effect to Shuriken)
1. Mirage: increase evasion by 100% for 3 seconds and deal 100 potency damage whenever an attack misses you), 60 sec CD, off-GCD
2. Katon: 100 potency; Additional effect: fire damage over time, potency 30 over 21 seconds; consumes Ill-gotten Gains, off-GCD
3. Raijin: 50 potency lightning damage; Additional effect: stun 5 seconds; off-GCD; consumes Ill-gotten Gains
4. Fuujin: 150 potency wind damage ranged AoE, consumes Ill-Gotten Gains
5. Grand Lethal: 300 potency non-elemental PbAoE; increases damage by 20% for 20 seconds; 180 sec CD
The Dancer is a healing job stemming from THF. It repurposes Gil Toss into an off-GCD heal, which, if needed could have its potency bumped up (potentially up to the same 400 as Cure). It uses both TP (for dancer abilities) and MP (for Cure/Physick, which would be maintenance healing). There isn't a stance to swap from damage to healing and DEX is still used as the healing stat because healers tend to hang out at range, and this class must close to melee, which is a much more dangerous location, in order to attack.
The DNC gets all of the requisite traits of a healer: a maintenance heal (Cure), a burst heal (Gil-Toss and Tango Finale), a cleanse (Kiss-kiss), and an AoE heal (Faerie Waltz, which is slightly faster and more powerful than Medica or Succor to make up for not having Medica II or Whispering Dawn to improve it). Jitterbug is a powerful support ability with high comparative uptime that also acts as a burst healing buff for the DNC. Sword Dance is a powerful hit that also acts allows you to get Ill-Gotten Gains at a drastically increased rate.
The relic would be the Dancing Dagger, a weapon of yore used as a by a famous dancer who served the sultan of Ul'dah as his favorite concubine. The sultan loved the dancer so much that, when she died defending him from assassins, the sultan entered a great malaise that threatened to kill him. His most loyal servants, desperate to give the sultan some reason to live again, enchanted the dancer's dagger to give whoever held it the ability to dance as she once did. Even so, the heartbroken sultan died, the dagger was placed in the sultan's vaults and forgotten.
Dancer Job Abilities (THF, ACN, CNJ):
(Gil Toss changes: targets ally, cure potency 200)
(Dexterity used to calculate healing potency)
1. Faerie Waltz: AoE heal, potency 350, consumes TP, 2.0 sec cast
2. Kiss-kiss: Cleanse, consumes TP, 1.0 sec cast
3. Jitterbug: Increase your skill and spell speed by 50 and the skill and spell speed of all allies within 20y by 20%, 15 second duration, 60 sec CD, off-GCD
4. Tango Finale: cure potency 400, heal over time potency 50, 18 sec duration, consumes TP, 2.5 sec cast
5. Sword Dance: attack potency 300, 15 sec CD, consumes TP, grants Ill-Gotten Gains
(Fundamental Assumptions: Dancer will take Cure or Physick to act as baseline ST heal and Resurrection as rez)