Well, since someone was nice enough to bump this thread, I'll repost something I put in the other musketeer thread. Either way none of this will matter in 5 days, but always fun to think of stuff:

Musketeer/銃術士
Mechanics - Musketeer can switch between pistol and musket, and some of their shots require one or the other.

Weapons - Kits: Kits are composed of pistol(s) and musket.

Abilities

01 Split Shot - Delivers two attacks with a potency of X per shot.
02 Hot Shot - Delivers an attack with a potency of X and places a DoT effect with a potency of X for 15 seconds. Additional Effect: Pistol.
04 Overcharge - Increases the cost of your next ability by 100% to make it a guaranteed critical. 2 minute cooldown.
06 Field Potion - Restores own HP. Cure potency 150. Potency scales with DEX. 2.5 second cast time. Can be cast while moving.
08 Trick Shot - Requires Pistol. Delivers an attack with a potency of X and one extra target with decreased potency.
10 Grenade - Delivers an area attack with a potency of 200. 4 yalm radius. 90-second cooldown.
12 Leg Shot - Places a 60% weight effect on enemy for 18 seconds. Weight potency decreases over time.
15 Aimed Shot - 2.5 second cast time. Delivers an attack with a potency of X. 10 second cooldown. Additional Effect: Musket.
18 Quickdraw - Changes your weapon from pistol to musket and vice versa. 10 second cooldown.
22 Barrage (MSK) - Requires Pistol. Channeled attack. Repeatedly shoot at target enemy over 9 seconds. 90 second cooldown.
26 Hair Trigger - Increases skill speed by 75%. 15 second duration. 2 minute cooldown.
30 Scattershot - Requires Musket. Delivers an attack with a potency of 100 to all enemies in a cone before you.
34 Gun and Run - Your next shot increases movement speed by 50% for 10 seconds.
38 Piercing Shot - Requires Pistol. Delivers an attack with a potency of X. Increases damage target takes from physical attacks by 10%. 25 second duration. 3 minute cooldown.
42 Tar Bomb - Creates a designated area in which enemies are afflicted with 30% weight. 18-second duration. 60-second cooldown.
46 Stock Strike - Stuns target enemy for 3 seconds. Requires melee range. 20-second cooldown.
50 Leaden Salute - Requires Musket. Delivers an attack with a potency of X. 3 seconds after target is affected, target explodes, dealing damage to all enemies near it.

Traits
08 Enhanced Dexterity (Musketeer) - Increases DEX by 2.
14 Quick Repeater - Your shots have a 15% chance to increase the potency of your next Split Shot.
16 Enhanced Dexterity II (Musketeer) - Increases DEX by 4.
20 Two-Gun - Allows the use of two pistols.
24 Ubercharge - Overcharge now increases the cost of your next ability by 75%.
28 Enhanced Grenade - Increases the radius of your grenades to 8 yalms.
32 Tactical Barrage - Increases TP regen rate while under the effect of Barrage (MSK).
36 Sniper Training - Your shots have a 10% chance to make your next Aimed Shot instant.
40 Enhanced Leg Shot - Your leg shot now places an 80% slow effect.
44 Enhanced Hair Trigger - Hair Trigger now increases skill speed by 150%.
50 Combustion - Using Hot Shot on enemies standing in a tar patch sets it on fire, dealing X potency damage every second for 6 seconds.

Achievements
Aim for the top, gun I-V: Attain musketeer level 10-50

Notes

* This musketeer is designed around built-in weapon swaps. I tried to make it as organic as possible, which is not an easy thing to do despite there being only two weapons.
* Part of why I decided "kits" should be MSK's weapon choice is because what we have seen so far are NOT muskets. They are flintlock pistols. Muskets are long-barreled weapons that were the precursor to the modern rifle, and it would be odd to call the double-barreled pistols the yellowjackets and Merlwyb use muskets.
* Kits also accomodate the MSK getting a second pistol to use once they hit lv20 without requiring additional weapons.
* The idea here is that your options are limited to the current weapon, with both weapons having roles within gameplay. Pistol shots are more for debuffing and minor damage, while musket shots are damage-focused. In doing so we'd be both accurate while also not letting the pistol models in-game go to waste.
* I do realize this would be more difficult to develop due to the need to animate two weapons. The best way (IMO) to unify the animations would be having both stand with the left foot front and the right foot back. When using a pistol the stance would be similar to that of how policemen pose/hold pistols (until you get the trait Two-Gun). The footwork happens to coincide with the posture used when firing a rifle/musket, so it would save the animators some time I would think.
* I have a feeling there should be some sort of benefit or mechanic to further encourage switches (like, say, being in pistol mode causes TP to regenerate faster while musket stops or greatly lowers TP regen or something). I'm just not too sure how to balance something like that.
* That said, I'll admit this concept was influenced a little by the gunners in Revelation Online and Lost Ark.

Chemist/アイテム士
Abilities
30 Combat Medic - Increases healing by X. Disables auto-attacks and prevents the use of abilities that switch you to or require Musket. Allows Split Shot and Barrage to be used on allies. Replaces Field Potion with Alchemist's Potion and Grenade with Mega-Potion Grenade. Effect ends upon reuse.
**Split Shot - Restores a little HP.
**Barrage - Restores HP over 9 seconds.
**Alchemist's Potion - Restores HP. 2.5 second cast time. Can be cast while moving.
**Mega-Potion Grenade - Restores HP of target and all allies within 8 yalms.
35 Remedy Dart - Removes one status ailment
40 Phoenix Pinion - Revives ally in a weakened state
45 Tranquilizer Dart - Puts target to sleep for 20 seconds (8 seconds in PvP)
50 Megalixir - Recovers 50% of target's max HP over 12 seconds

Quests
30 Practical Medicine
35 In the name of science
40 Affable Apothecaries
45 Unwanted Side-effects
50 A teaspoon of sugar...
50 A Relic Reborn: Mercury kit => Asclepius (final form)

Achivements
I bring them healing bullets - Complete the chemist job quest "A teaspoon of sugar..."
By the power of medicine - Obtain a mercury kit in the quest A Relic Reborn

Notes

* Chemist is designed around being more mobile than WHM or SCH.
* A CHM's options for healing would be Split Shot, Barrage for focused healing, Mega-Potion Grenade for AOE heals and Alchemist's Potion as their standard "cure"-type ability.
* Because CHM's main heal can be case while moving, I figure overall healing throughput should be split between Split Shot's healing bullets, alchemist's potion and what uptime is possible with Barrage.

Gunner/ガンナー
Abilities
30 Mortal Shot - Requires Musket. Delivers an attack with a potency of 200. Can only be used when target's HP is below 30%. 15 Second cooldown.
35 Quickshot - Delivers an attack with a potency of 10. Additional Effect: Silence. 35 second cooldown.
40 Juggle - Requires Pistol. Requires melee range. Delivers a channeled attack that slowly pushes target away from you. Additional Effect: Pacification.
45 Explosive Rounds - Your next 3 shots deal additional fire damage to target and enemies within 2 yalms.
50 Marked for Death - Increases physical damage taken by target by 10%. 2 minute cooldown.

Quests
30 The big iron
35 A gun gone gung-ho
40 On honeyed words
45 Arms of the angels
50 Showdown at high noon
50 A Relic Reborn: Exeter Kit => Fomalhaut Kit (final form).

Achivements
Three-Gun - Complete the gunner job quest "Showdown at high noon"
Arms gone wild - Obtain an exeter kit in the quest A Relic Reborn.

Notes

* I'm not ashamed to say I was thinking of westerns too much while coming up with the quests for gunner.
* I'm also not ashamed to say I'd want the AF would be something along the lines of what we saw with Vash the Stampede or Dante from Devil May Cry.
* With the above in mind, Juggle is meant to be a peeling ability that also does damage but puts you at risk since you have to stand still. As far as where I got the idea for juggle...well... (yes, I'm aware it looks silly)